---
title: "Słownik pojęć"
url: "https://nodea.io/en/glossary"
lang: "en"
---

# Słownik pojęć

## Entries

- [.htaccess](https://nodea.io/en/glossary/htaccess.md): The .htaccess file configures the Apache server per directory: redirects, pretty URLs, password protection and headers. Learn its syntax and common uses.
- [301 redirect](https://nodea.io/en/glossary/301-redirect.md): A 301 redirect is a permanent URL redirect that passes link equity and affects SEO. Learn how it works and when to use it for moving content.
- [302 redirect](https://nodea.io/en/glossary/302-redirect.md): A 302 redirect is a temporary URL redirect that keeps SEO value with the original address. Learn how it works and when to use it instead of a 301.
- [401 error (Unauthorized)](https://nodea.io/en/glossary/http-401-error.md): The HTTP 401 Unauthorized error means the request lacks valid authentication. Learn what triggers it, how to fix it and how it differs from the 403 error.
- [403 error (Forbidden)](https://nodea.io/en/glossary/http-403-error.md): The HTTP 403 Forbidden error means the server refuses access to a resource. Review the usual causes — file permissions, .htaccess, WAF blocks — and fixes.
- [404 error (Not Found)](https://nodea.io/en/glossary/http-404-error.md): The HTTP 404 error says no resource exists at a given URL. Learn where 404s come from, how they affect SEO and when a 301 redirect is the right answer.
- [408 error (Request Timeout)](https://nodea.io/en/glossary/http-408-error.md): The HTTP 408 error appears when a client fails to send its request within the server's time limit. See common causes, fixes and how 408 differs from 504.
- [500 error (Internal Server Error)](https://nodea.io/en/glossary/http-500-error.md): The HTTP 500 error signals an unexpected server-side failure. Learn the usual suspects — PHP errors, .htaccess, memory limits — and how to read logs.
- [A record](https://nodea.io/en/glossary/a-record.md): An A record maps a domain name to a server's IPv4 address. Learn its structure, the role of TTL and how it is used when pointing domains and migrating.
- [A/B testing](https://nodea.io/en/glossary/a-b-testing.md): A/B testing compares two versions of a page or element to see which performs better, using real user data. See how it removes guesswork from optimisation.
- [AAAA record](https://nodea.io/en/glossary/aaaa-record.md): An AAAA record maps a domain to a server's IPv6 address. Learn how it differs from an A record, its structure and its role in IPv6 reachability.
- [ABM (Account-Based Marketing)](https://nodea.io/en/glossary/account-based-marketing.md): ABM (Account-Based Marketing) is a B2B strategy where marketing and sales target personalized campaigns at a few high-value accounts. Learn the definition.
- [Above the fold (ATF)](https://nodea.io/en/glossary/above-the-fold.md): Above the fold (ATF) is the part of a page visible without scrolling. Learn why it drives conversions, ties into LCP and shapes the first impression.
- [Absolute link](https://nodea.io/en/glossary/absolute-link.md): An absolute link is a full URL with protocol and domain. Learn how absolute links differ from relative links and where each type belongs in practice.
- [Ad groups](https://nodea.io/en/glossary/ad-groups.md): Ad groups are the Google Ads layer that ties keywords to ads around one theme. Learn their role, structure and how good segmentation improves results.
- [Adware](https://nodea.io/en/glossary/adware.md): Adware is software that displays intrusive ads and often tracks user activity. Learn how it works, the risks it poses, and how to protect against it.
- [Affiliate Marketing](https://nodea.io/en/glossary/affiliate-marketing.md): Affiliate marketing is a model where a partner earns commission for sales or actions generated by their referral. Learn the payout models and its uses.
- [Agile](https://nodea.io/en/glossary/agile.md): Agile is an iterative approach to software development built on collaboration and fast response to change. Learn its values, methods, and practical uses.
- [Ahrefs](https://nodea.io/en/glossary/ahrefs.md): Ahrefs is a popular SEO tool for analyzing backlink profiles, keywords, and competitors. Learn its features, the DR/UR metrics, and its practical uses.
- [AI (Artificial Intelligence)](https://nodea.io/en/glossary/artificial-intelligence.md): AI (artificial intelligence) is the field of computer science building systems able to perform tasks requiring intelligence. Learn its types and uses.
- [AI Detector](https://nodea.io/en/glossary/ai-detector.md): An AI detector estimates whether text was written by a human or generated by artificial intelligence. Learn how it works and its limitations.
- [AI Overviews](https://nodea.io/en/glossary/ai-overviews.md): AI Overviews are AI-generated answer summaries shown at the top of Google results. Learn how they work and what they mean for SEO and website traffic.
- [AIDA (marketing model)](https://nodea.io/en/glossary/aida-model.md): AIDA is a classic marketing model describing four stages: Attention, Interest, Desire, Action. Learn each phase and its use in copywriting and advertising.
- [AJAX](https://nodea.io/en/glossary/ajax.md): AJAX is a technique that lets web pages exchange data with the server without reloading the page. Learn how it works and the role of JavaScript.
- [Algorithm](https://nodea.io/en/glossary/algorithm.md): An algorithm is a finite, ordered sequence of steps that solves a problem. Learn the definition, the traits of a good algorithm, and its uses in SEO.
- [Alt attribute](https://nodea.io/en/glossary/alt-attribute.md): The alt attribute is an image's alternative text in HTML. Learn its role in accessibility, image SEO and what shows when a graphic fails to load.
- [AMP](https://nodea.io/en/glossary/amp.md): AMP (Accelerated Mobile Pages) is a framework for near-instant mobile page loads. See how AMP HTML, AMP JS and the AMP Cache work, and if it's worth it.
- [Anchor text](https://nodea.io/en/glossary/anchor-text.md): Anchor text is the clickable text of a hyperlink. See the main anchor types, how search engines read them, and how to keep your link profile natural.
- [Angular](https://nodea.io/en/glossary/angular.md): Angular is Google's TypeScript framework for building single-page applications. Learn how components, dependency injection and the CLI work in practice.
- [Ansible](https://nodea.io/en/glossary/ansible.md): Ansible automates server configuration and app deployment over SSH with no agents. See how inventories, playbooks, modules and roles fit together.
- [Apache](https://nodea.io/en/glossary/apache.md): Apache HTTP Server is a modular open-source web server powering much of the web. See how MPMs, modules and .htaccess work and when to pick it over Nginx.
- [Apache Kafka](https://nodea.io/en/glossary/apache-kafka.md): Apache Kafka is a distributed event streaming platform built on partitioned logs. See how topics, brokers and consumer groups work and where Kafka fits.
- [API](https://nodea.io/en/glossary/api.md): An API is a contract that lets applications exchange data and functionality. Learn how REST, SOAP and GraphQL APIs work, plus auth and rate limits.
- [Apilo](https://nodea.io/en/glossary/apilo.md): Apilo is a Polish multichannel e-commerce hub that unifies marketplace and online store orders in one panel. Learn how its sync, invoicing and API work.
- [APM](https://nodea.io/en/glossary/apm.md): APM tracks application performance from the inside: response times, traces, slow SQL and errors. Learn how agents, spans and alerting work in practice.
- [Application](https://nodea.io/en/glossary/application.md): An application is software built to perform user tasks. Compare desktop, mobile, web and progressive web apps, and see what each needs in production.
- [ARC](https://nodea.io/en/glossary/arc.md): ARC preserves SPF and DKIM verification results when email passes through forwarders and mailing lists. See how the three ARC headers build a trust chain.
- [ASP.NET](https://nodea.io/en/glossary/asp-net.md): ASP.NET is Microsoft's framework for building web apps and APIs in C#. See how ASP.NET Core, Kestrel, Razor Pages and Blazor work and how to host them.
- [Assembly](https://nodea.io/en/glossary/assembly-language.md): Assembly is a low-level language where each instruction maps to a CPU operation. Learn how assemblers work and where assembly still matters today.
- [Attribution](https://nodea.io/en/glossary/attribution.md): Attribution assigns credit for a conversion across a customer's touchpoints. Learn the main attribution models and how they shape ad budget decisions.
- [AuthInfo code](https://nodea.io/en/glossary/authinfo-code.md): The AuthInfo (EPP) code is a unique password authorizing a domain transfer between registrars. Learn how to get it and how it prevents domain hijacking.
- [Autoresponder](https://nodea.io/en/glossary/autoresponder.md): An autoresponder is a system that automatically sends scheduled emails. Learn its uses in marketing, customer service and welcome sequences.
- [AVIF](https://nodea.io/en/glossary/avif.md): AVIF is a modern, highly compressed image format based on the AV1 codec. Learn its benefits, browser support and its impact on page load speed.
- [B2B (Business to Business)](https://nodea.io/en/glossary/b2b.md): B2B (business to business) is a model where a company sells to other companies. Learn the traits of B2B selling and how it differs from B2C commerce.
- [B2C (Business to Consumer)](https://nodea.io/en/glossary/b2c.md): B2C (business to consumer) is a model where companies sell directly to consumers. Learn the traits of B2C buying and how it differs from B2B commerce.
- [Babel](https://nodea.io/en/glossary/babel.md): Babel is a JavaScript transpiler that converts modern code into versions compatible with older browsers. Learn how it works and its build role.
- [Backbone.js](https://nodea.io/en/glossary/backbone-js.md): Backbone.js is a lightweight JavaScript framework giving apps structure via models, collections and views. Learn how it works and its SPA legacy.
- [Backend](https://nodea.io/en/glossary/backend.md): The backend is the server-side layer of an app, invisible to users. Learn its role, parts like server, database and API, and how it differs from frontend.
- [Backend developer](https://nodea.io/en/glossary/backend-developer.md): A backend developer builds the server-side layer of an app: logic, APIs and databases. Learn their tasks, technologies and role within the team.
- [Backlink](https://nodea.io/en/glossary/backlink.md): A backlink is a link from one site pointing to another. Learn its role in SEO, what makes a valuable backlink and how dofollow differs from nofollow.
- [Backlog](https://nodea.io/en/glossary/backlog.md): A backlog is a prioritized list of tasks, features and fixes a team plans to deliver. Learn how product and sprint backlogs work in Scrum and Agile teams.
- [Backup](https://nodea.io/en/glossary/backup.md): A backup is a secondary copy of data kept for recovery after failure, ransomware or human error. Learn backup types, the 3-2-1 rule and restore testing.
- [Bandwidth](https://nodea.io/en/glossary/bandwidth.md): Bandwidth is the maximum data rate a network link can carry per second. Learn how it differs from throughput and transfer, its units and performance impact.
- [BCC](https://nodea.io/en/glossary/bcc.md): BCC (blind carbon copy) sends an email copy to recipients whose addresses stay hidden from everyone else. See when to use it and its privacy role.
- [BEdita](https://nodea.io/en/glossary/bedita.md): BEdita is an open-source, API-first headless CMS built on CakePHP, serving content over a JSON:API REST interface. See how it works and when to choose it.
- [Bidding strategies](https://nodea.io/en/glossary/bidding-strategies.md): Bidding strategies are the ways ad platforms place bids in auctions. Learn manual vs automated bidding, campaign goals and how to match a model to your business.
- [Big data](https://nodea.io/en/glossary/big-data.md): Big data means datasets too large, fast and varied for classic tools. Explore the 3V/5V model, distributed processing and how firms turn data into value.
- [BIMI](https://nodea.io/en/glossary/bimi.md): BIMI displays a verified brand logo next to your emails in Gmail or Yahoo. Learn the requirements: DMARC enforcement, an SVG logo and a VMC certificate.
- [Bing](https://nodea.io/en/glossary/bing.md): Bing is Microsoft's search engine, built into Windows, Edge and Copilot. Learn how Bingbot and IndexNow work and how to optimize your site for Bing.
- [Bitmap](https://nodea.io/en/glossary/bitmap.md): A bitmap is an image stored as a grid of pixels — the format behind JPEG, PNG and WebP photos. Learn how raster graphics work and differ from vectors.
- [Black hat SEO](https://nodea.io/en/glossary/black-hat-seo.md): Black hat SEO covers ranking tactics that break search engine guidelines — cloaking, keyword stuffing, link spam. See the risks: penalties and deindexing.
- [Blast](https://nodea.io/en/glossary/email-blast.md): An email blast is a single mass mailing sent to an entire subscriber list at once. Learn when blasts make sense and how to protect deliverability.
- [Blazor](https://nodea.io/en/glossary/blazor.md): Blazor is Microsoft's framework for building interactive web UIs in C# instead of JavaScript, running via WebAssembly or on the server through SignalR.
- [Blockchain](https://nodea.io/en/glossary/blockchain.md): Blockchain is a distributed, append-only ledger where records live in cryptographically linked blocks. See how consensus works and where it is used.
- [Bolt CMS](https://nodea.io/en/glossary/bolt-cms.md): Bolt CMS is a lightweight open-source content management system built on Symfony and Twig. Learn how its content types work and what hosting it needs.
- [Bootstrap](https://nodea.io/en/glossary/bootstrap.md): Bootstrap is an open-source CSS framework with a responsive grid, ready-made components and utility classes. See how it speeds up building web UIs.
- [Bounce rate](https://nodea.io/en/glossary/bounce-rate.md): Bounce rate is the share of visits that end without any interaction. Learn how GA4 measures it via engaged sessions and how to lower it effectively.
- [Branding](https://nodea.io/en/glossary/branding.md): Branding is the deliberate process of shaping a brand's identity, image and associations. Explore its strategic, verbal and visual layers in practice.
- [Brandmark](https://nodea.io/en/glossary/brandmark.md): A brandmark is a graphic symbol that identifies a brand without its name — think Apple's apple or Nike's swoosh. See how it differs from a logotype.
- [Breadcrumbs](https://nodea.io/en/glossary/breadcrumbs.md): Breadcrumbs are a navigation trail showing the path from the homepage to the current page. Learn how they improve UX, SEO and search result snippets.
- [Brief](https://nodea.io/en/glossary/brief.md): A brief is a document that hands an agency or contractor the goals, audience, scope and constraints of a project. See what a good brief must contain.
- [Broad Match](https://nodea.io/en/glossary/broad-match.md): Broad match is the widest keyword match type in Google Ads, showing ads for related searches. Learn how it works, when to use it and how to control spend.
- [Brotli](https://nodea.io/en/glossary/brotli.md): Brotli is Google's lossless compression algorithm that shrinks web assets 15–25% more than gzip. Learn how to enable it on Nginx, Apache and CDNs.
- [Brute force](https://nodea.io/en/glossary/brute-force-attack.md): A brute force attack cracks passwords by trying combinations until one works. Learn the attack variants and how to protect servers and login forms.
- [Buffer](https://nodea.io/en/glossary/buffer.md): A buffer is a memory area holding data temporarily while it moves between processes or devices of different speeds. See how buffering works in practice.
- [Bug](https://nodea.io/en/glossary/bug.md): A bug is a defect in software that makes a program behave incorrectly or crash. Learn the main bug types, the bug life cycle and how teams find them.
- [Bug bounty](https://nodea.io/en/glossary/bug-bounty.md): A bug bounty program pays security researchers for responsibly reported vulnerabilities. See how scopes, rewards and triage work in practice.
- [Bumper ads](https://nodea.io/en/glossary/bumper-ads.md): Bumper ads are six-second, non-skippable YouTube video ads billed per thousand impressions. Learn how they work and when to add them to a campaign.
- [Buyer persona](https://nodea.io/en/glossary/buyer-persona.md): A buyer persona is a semi-fictional, research-based profile of your ideal customer. See what it includes and how to use it in marketing and sales.
- [C2C (consumer-to-consumer)](https://nodea.io/en/glossary/c2c.md): C2C (consumer-to-consumer) is a commerce model where private individuals trade via marketplaces. Learn how C2C platforms work, earn and build trust.
- [CAA record](https://nodea.io/en/glossary/caa-record.md): A CAA record specifies which certificate authorities may issue SSL certificates for your domain. Learn its structure and its role in domain security.
- [CAC (Customer Acquisition Cost)](https://nodea.io/en/glossary/customer-acquisition-cost.md): Customer Acquisition Cost (CAC) is what you spend on marketing and sales per new customer. Learn the formula, the LTV:CAC ratio and how to reduce CAC.
- [Cache and microcaching](https://nodea.io/en/glossary/cache-and-microcaching.md): Caching stores ready-made responses to avoid regenerating them; microcaching buffers dynamic pages for 1–10 seconds. See how both protect your server.
- [Cache-Control](https://nodea.io/en/glossary/cache-control.md): Cache-Control is the HTTP header that tells browsers and CDNs whether and how long to cache a response. Learn max-age, no-store, immutable and more.
- [CakePHP](https://nodea.io/en/glossary/cakephp.md): CakePHP is a mature open-source PHP framework built on MVC and convention over configuration. Learn its ORM, bake scaffolding and typical use cases.
- [Callout Extension](https://nodea.io/en/glossary/callout-extension.md): A Google Ads callout extension adds short, non-clickable phrases below an ad. Learn how it works, see example copy and its impact on click-through rate.
- [Canonical tag](https://nodea.io/en/glossary/canonical-tag.md): The canonical tag tells search engines which version of a page is preferred, solving duplicate content issues. Learn rel=canonical syntax and use cases.
- [Canva](https://nodea.io/en/glossary/canva.md): Canva is a browser-based design tool with drag-and-drop editing and thousands of templates for social posts, presentations and marketing graphics.
- [CAPTCHA](https://nodea.io/en/glossary/captcha.md): CAPTCHA is a challenge that separates humans from bots — from distorted text to invisible risk scoring. See how modern CAPTCHAs work and when to use them.
- [Case study](https://nodea.io/en/glossary/case-study.md): A case study documents a real client's problem, the solution delivered and measurable results. Learn the structure that makes case studies convert.
- [CC (Carbon Copy)](https://nodea.io/en/glossary/cc-carbon-copy.md): CC (carbon copy) is the email field for visible recipients who get a copy for information. Learn how CC differs from BCC and how to use it correctly.
- [CDN (Content Delivery Network)](https://nodea.io/en/glossary/cdn.md): A CDN is a distributed network of edge servers that serves your content from the location nearest each visitor. Learn how it cuts latency and stops DDoS.
- [Chamilo](https://nodea.io/en/glossary/chamilo.md): Chamilo is a free, open-source LMS written in PHP for running online courses, quizzes and corporate training. See its features and hosting needs.
- [Chaos engineering](https://nodea.io/en/glossary/chaos-engineering.md): Chaos engineering injects controlled failures into systems to verify resilience before real outages strike. Learn the method, tools and safety rules.
- [CI/CD](https://nodea.io/en/glossary/ci-cd.md): CI/CD automates building, testing and deploying code. Learn how continuous integration differs from continuous delivery and where these pipelines are used.
- [Cisco](https://nodea.io/en/glossary/cisco.md): Cisco is a maker of networking gear: routers, switches and firewalls. Learn the role of Cisco devices in corporate networks and data center infrastructure.
- [Citation Flow](https://nodea.io/en/glossary/citation-flow.md): Citation Flow is a Majestic metric measuring the quantitative strength of a site's links. Learn how it differs from Trust Flow and its use in SEO analysis.
- [CLI](https://nodea.io/en/glossary/cli.md): CLI is a command line interface where you control a system by typing text commands. Learn how it works and where CLI is used in server administration.
- [Clickbait](https://nodea.io/en/glossary/clickbait.md): Clickbait is a technique of writing headlines that exaggerate content to force a click. Learn the mechanism, SEO risks and the line versus a fair title.
- [Cloaking](https://nodea.io/en/glossary/cloaking.md): Cloaking is a Black Hat SEO technique of serving different content to Google's bots than to users. Learn the mechanism, examples and the penalties.
- [Cloud](https://nodea.io/en/glossary/cloud.md): Cloud computing is an on-demand model for accessing IT resources over the internet. Learn the IaaS, PaaS and SaaS models and how the cloud is used.
- [CLS](https://nodea.io/en/glossary/cls.md): CLS (Cumulative Layout Shift) is a Core Web Vitals metric measuring visual stability. Learn what causes layout shifts and how to eliminate them.
- [Cluster](https://nodea.io/en/glossary/cluster.md): A cluster is a group of servers acting as one system to deliver high availability and scalability. Learn the types of clusters and their uses.
- [CMS](https://nodea.io/en/glossary/cms.md): A CMS is a content management system that lets you build and edit sites without coding. Learn how it works, popular examples and practical uses.
- [CNAME record](https://nodea.io/en/glossary/cname-record.md): A CNAME record is an alias pointing one domain name to another canonical name. Learn how it works, its limitations and its typical uses.
- [CodeIgniter](https://nodea.io/en/glossary/codeigniter.md): CodeIgniter is a lightweight MVC PHP framework valued for simplicity and speed. Learn its architecture, benefits and typical uses in web applications.
- [Compilation](https://nodea.io/en/glossary/compilation.md): Compilation is translating source code into an executable form by a compiler. Learn the stages of the process and how it differs from interpretation.
- [Component](https://nodea.io/en/glossary/component.md): A component is a self-contained, reusable building block of an application. Learn how components work, their interface and where they are used in practice.
- [Concrete5](https://nodea.io/en/glossary/concrete5.md): Concrete5 (Concrete CMS) is a content management system with editing directly on the page. Learn how it works, its block model and typical uses.
- [Contao](https://nodea.io/en/glossary/contao.md): Contao is an open-source CMS valued for accessibility, clean code and a robust permission system. Learn how it works and its typical uses on sites.
- [Content marketing](https://nodea.io/en/glossary/content-marketing.md): Content marketing is a strategy of building audience relationships through valuable content. Learn its mechanism, formats and practical uses.
- [Conversion](https://nodea.io/en/glossary/conversion.md): A conversion is a visitor completing a desired action on your site. Learn conversion types, the conversion rate and how to optimize it in practice.
- [Cookies](https://nodea.io/en/glossary/cookies.md): Cookies are small files stored by the browser that hold session and preference data. Learn their types, how they work and their privacy implications.
- [Coppermine Photo Gallery](https://nodea.io/en/glossary/coppermine-photo-gallery.md): Coppermine Photo Gallery is an open-source PHP script for building online photo galleries. Learn its features, how it works and typical uses on a site.
- [Core Web Vitals](https://nodea.io/en/glossary/core-web-vitals.md): Core Web Vitals are Google's key metrics for loading speed, interactivity and visual stability. Learn what LCP, INP and CLS measure and how to pass them.
- [CPA (Cost Per Action)](https://nodea.io/en/glossary/cpa-cost-per-action.md): CPA (Cost Per Action) means you pay for ads only when users complete a defined action, like a purchase or sign-up. See the formula and ways to lower CPA.
- [CPC (Cost Per Click)](https://nodea.io/en/glossary/cpc-cost-per-click.md): CPC (Cost Per Click) is the ad model where you pay per click, not per impression. Learn the formula, what drives click prices and how to lower your CPC.
- [CPL (Cost Per Lead)](https://nodea.io/en/glossary/cpl-cost-per-lead.md): CPL (Cost Per Lead) measures how much you pay for each prospect's contact details. Learn the formula, typical use cases and how to bring your CPL down.
- [CPM (Cost Per Mille)](https://nodea.io/en/glossary/cpm-cost-per-mille.md): CPM (Cost Per Mille) is the price paid per 1,000 ad impressions — the standard model for reach and display campaigns. See the formula and when to use it.
- [CPV (Cost Per View)](https://nodea.io/en/glossary/cpv-cost-per-view.md): CPV (Cost Per View) is the video ad model where you pay only when someone actually watches your ad. Learn view thresholds, formulas and optimization tips.
- [Crawler](https://nodea.io/en/glossary/crawler.md): A crawler is an automated bot that visits web pages, follows links and collects content for search indexes. Learn how crawlers work and how to manage them.
- [Cron](https://nodea.io/en/glossary/cron.md): Cron is the background daemon on Unix and Linux systems that runs commands on a schedule. Learn the five-field time syntax and common server use cases.
- [Cron job](https://nodea.io/en/glossary/cron-job.md): A cron job is a single recurring task run by the cron daemon — backups, log cleanup, queue processing. See examples and best practices for reliability.
- [Crontab](https://nodea.io/en/glossary/crontab.md): Crontab is both the file holding a user's cron schedule and the command to manage it. Learn crontab -e, -l and -r, entry syntax and environment variables.
- [Cross-browser compatibility](https://nodea.io/en/glossary/cross-browser-compatibility.md): Cross-browser compatibility means your site works correctly in Chrome, Firefox, Safari and Edge alike. Learn the techniques and tools that make it happen.
- [Cross-selling](https://nodea.io/en/glossary/cross-selling.md): Cross-selling means offering customers products that complement their purchase — a case with a phone, SSL with a domain. See tactics that lift order value.
- [CSAT (Customer Satisfaction Score)](https://nodea.io/en/glossary/csat-customer-satisfaction-score.md): CSAT (Customer Satisfaction Score) measures how happy customers are with a specific interaction, on a simple 1–5 scale. Learn the formula and best uses.
- [CSRF (Cross-Site Request Forgery)](https://nodea.io/en/glossary/csrf-cross-site-request-forgery.md): CSRF tricks a logged-in user's browser into sending forged requests to a trusted site. Learn the attack mechanics, CSRF tokens and SameSite protection.
- [CSS (Cascading Style Sheets)](https://nodea.io/en/glossary/css.md): CSS (Cascading Style Sheets) is the language that styles web pages — layout, color, typography and animation. Learn how the cascade and selectors work.
- [CSS Grid](https://nodea.io/en/glossary/css-grid.md): CSS Grid is a two-dimensional layout system that splits a page into columns and rows. Learn how it works, its properties and how it differs from Flexbox.
- [CTA (call to action)](https://nodea.io/en/glossary/call-to-action.md): A CTA (call to action) is a button or link that prompts users to act — buy, sign up, download. Learn how to design CTAs that lift conversion rates.
- [CTR (click-through rate)](https://nodea.io/en/glossary/click-through-rate.md): CTR (click-through rate) is the ratio of clicks to impressions, shown as a percentage. See how to calculate it and improve CTR in search and ads.
- [Customer experience](https://nodea.io/en/glossary/customer-experience.md): Customer experience (CX) is the sum of every interaction a customer has with a brand. Learn how to map, measure and improve CX to grow retention.
- [Customer insight](https://nodea.io/en/glossary/customer-insight.md): Customer insight is an evidence-based understanding of why customers behave the way they do. Learn where insights come from and how to act on them.
- [Dark post](https://nodea.io/en/glossary/dark-post.md): A dark post is a social media ad that never appears on the brand's profile — only targeted audiences see it. See how dark posts work and when to use them.
- [Darknet](https://nodea.io/en/glossary/darknet.md): The darknet is a hidden part of the internet reachable only via tools like Tor. Learn how onion routing works, darknet vs deep web, and the real risks.
- [Data](https://nodea.io/en/glossary/data.md): Data means raw facts and values stored in a processable form. Learn the difference between data and information, data types, and protection basics.
- [Data lake](https://nodea.io/en/glossary/data-lake.md): A data lake stores raw data of any format at any scale, applying structure only on read. See how it works and how it differs from a data warehouse.
- [Data science](https://nodea.io/en/glossary/data-science.md): Data science combines statistics, programming and domain knowledge to extract insight from data. Explore the workflow, tools and real applications.
- [Database](https://nodea.io/en/glossary/database.md): A database is a structured collection of data managed by a DBMS. Understand how relational (SQL) and NoSQL databases work and where each type fits best.
- [DDD (Domain-Driven Design)](https://nodea.io/en/glossary/domain-driven-design.md): DDD (Domain-Driven Design) aligns code with the business domain via ubiquitous language, bounded contexts and aggregates. See when it pays off.
- [DDoS](https://nodea.io/en/glossary/ddos.md): A DDoS attack floods a server with traffic from thousands of hijacked devices to knock it offline. Learn attack types and how layered defense works.
- [Debian](https://nodea.io/en/glossary/debian.md): Debian is a community-run Linux distribution famous for stability, powering web servers worldwide and serving as the base for Ubuntu. Learn how it works.
- [Debugging](https://nodea.io/en/glossary/debugging.md): Debugging is the process of locating and fixing bugs in software. Learn breakpoint debugging, log analysis, bisection and habits that speed it up.
- [Deliverability](https://nodea.io/en/glossary/email-deliverability.md): Email deliverability is the ability of messages to reach the inbox instead of spam. Learn what affects it and how SPF, DKIM and DMARC improve results.
- [Demand gen](https://nodea.io/en/glossary/demand-generation.md): Demand generation creates awareness and buying intent before prospects start searching. See how demand gen differs from lead gen and how to measure it.
- [Deploy](https://nodea.io/en/glossary/deployment.md): Deployment is the process of shipping a new application version to a server. Learn the stages, rollback options and strategies like blue-green and canary.
- [DevOps](https://nodea.io/en/glossary/devops.md): DevOps unites software development and IT operations through automation, CI/CD and shared ownership. See its core pillars, tools and business benefits.
- [Digital Accessibility](https://nodea.io/en/glossary/digital-accessibility.md): Digital accessibility means building websites and apps that people with disabilities can use. Learn the WCAG principles and the legal duties.
- [DirectAdmin](https://nodea.io/en/glossary/directadmin.md): DirectAdmin is a lightweight hosting control panel for managing domains, email, databases, SSL and backups from a browser. Learn its features and tiers.
- [Disavow Tool](https://nodea.io/en/glossary/disavow-tool.md): The Disavow Tool tells Google to ignore selected backlinks when evaluating your site. Learn the file format, valid use cases and the risks of overuse.
- [DKIM](https://nodea.io/en/glossary/dkim.md): DKIM signs outgoing email with a cryptographic key so receivers can verify the sender's domain. See how signatures, selectors and DNS records fit together.
- [DM](https://nodea.io/en/glossary/direct-message.md): A DM is a private message exchanged between users on social platforms like Instagram or X. See how DMs work and how brands use them for support and sales.
- [DMARC](https://nodea.io/en/glossary/dmarc.md): DMARC ties SPF and DKIM into a DNS-published policy telling receivers how to treat spoofed mail. Learn alignment, none/quarantine/reject and reporting.
- [DNS](https://nodea.io/en/glossary/dns.md): DNS is the distributed system that translates domain names into IP addresses. Learn how resolution works, common record types, caching and TTL.
- [DNS propagation](https://nodea.io/en/glossary/dns-propagation.md): DNS propagation is the time it takes for record changes to spread across DNS servers worldwide. Learn why it happens and how to speed it up.
- [DNS Server](https://nodea.io/en/glossary/dns-server.md): A DNS server answers domain name queries and returns the matching IP addresses. Learn the difference between recursive, authoritative and caching servers.
- [DNSSEC](https://nodea.io/en/glossary/dnssec.md): DNSSEC adds cryptographic signatures to DNS so resolvers can detect forged records and cache poisoning. Learn the chain of trust, DS records and caveats.
- [Docker](https://nodea.io/en/glossary/docker.md): Docker packages applications with all dependencies into portable containers that run identically everywhere. See images, Dockerfile, Compose and use cases.
- [DoH](https://nodea.io/en/glossary/dns-over-https.md): DoH tunnels DNS queries inside encrypted HTTPS traffic, hiding them from network observers. See how it works, how it differs from DoT, and its trade-offs.
- [Dolphin PHP](https://nodea.io/en/glossary/dolphin-php.md): Dolphin PHP (BoonEx Dolphin) is an open-source PHP script for building community sites with profiles, groups and media. See features and its status today.
- [Domain Authority](https://nodea.io/en/glossary/domain-authority.md): Domain Authority (DA) is Moz's 1–100 score predicting how well a domain can rank. Learn how DA is calculated, what moves it and how to use it in SEO.
- [Domain ownership transfer (assignment)](https://nodea.io/en/glossary/domain-ownership-transfer.md): A domain ownership transfer assigns registrant rights to a new person or company without changing the registrar. See the process, timing and safeguards.
- [Domain Rating](https://nodea.io/en/glossary/domain-rating.md): Domain Rating (DR) is Ahrefs' 0–100 score measuring the strength of a domain's backlink profile. See how it's calculated and how to read it in SEO.
- [DoT (DNS over TLS)](https://nodea.io/en/glossary/dns-over-tls.md): DoT (DNS over TLS) encrypts DNS queries inside a TLS tunnel on port 853. Learn how it works, how it differs from DoH and where it is applied.
- [Double Opt-in](https://nodea.io/en/glossary/double-opt-in.md): Double opt-in is a two-step email sign-up with an email confirmation link. Learn how it improves list quality, deliverability and consent compliance.
- [Dropdown Menu](https://nodea.io/en/glossary/dropdown-menu.md): A dropdown menu hides a list of options behind a button or nav item and reveals them on interaction. Learn how it works and the UX best practices.
- [Dropshipping](https://nodea.io/en/glossary/dropshipping.md): Dropshipping is an e-commerce model where the store sells products shipped directly by a supplier. Learn how it works, its advantages and its challenges.
- [DRP (Digital Risk Protection)](https://nodea.io/en/glossary/digital-risk-protection.md): DRP (Digital Risk Protection) monitors the open web and dark web for threats to a brand. Learn how it works and where it fits in cybersecurity.
- [Drupal](https://nodea.io/en/glossary/drupal.md): Drupal is a flexible open-source PHP CMS for building complex sites and portals. Learn its modular architecture, modules and typical use cases.
- [Duplicate Content](https://nodea.io/en/glossary/duplicate-content.md): Duplicate content is identical or near-identical content under different URLs. Learn its SEO impact and how to fix it with canonical tags and redirects.
- [Dwell Time](https://nodea.io/en/glossary/dwell-time.md): Dwell time is how long a user stays on a page after clicking a search result before returning to the SERP. Learn how it relates to content quality.
- [Dynamic Search Ads (DSA)](https://nodea.io/en/glossary/dynamic-search-ads.md): Dynamic Search Ads (DSA) are Google Ads generated automatically from your website content, without keywords. Learn how they work and where to use them.
- [e107](https://nodea.io/en/glossary/e107.md): e107 is a free open-source CMS built in PHP and MySQL for portals and news-driven sites. Learn its architecture, plugins, hosting needs and use cases.
- [E2E (end-to-end testing)](https://nodea.io/en/glossary/e2e-testing.md): End-to-end (E2E) tests validate an application as a whole by simulating real user actions from the UI to the database. Learn the concept, tools and role.
- [Easter egg](https://nodea.io/en/glossary/easter-egg.md): An Easter egg is a hidden surprise in software, a game or a website, triggered by a secret action. Learn its origins, examples and practical uses.
- [Elasticsearch](https://nodea.io/en/glossary/elasticsearch.md): Elasticsearch is a distributed full-text search and analytics engine built on Lucene. Learn about indexes, cluster architecture and common use cases.
- [Email Alias](https://nodea.io/en/glossary/email-alias.md): An email alias is an extra address that forwards messages to an existing mailbox without a new account. Learn how it works and where it is used.
- [Email marketing](https://nodea.io/en/glossary/email-marketing.md): Email marketing is direct communication with subscribers by email. Learn about consent, deliverability, segmentation and measuring campaign performance.
- [Email template](https://nodea.io/en/glossary/email-template.md): An email template is a reusable message layout with a fixed design and editable content. See how templates keep campaigns consistent and render everywhere.
- [Ember.js](https://nodea.io/en/glossary/ember-js.md): Ember.js is an opinionated JavaScript framework for building ambitious single-page web apps. Learn its conventions, architecture, routing and use cases.
- [European Accessibility Act](https://nodea.io/en/glossary/european-accessibility-act.md): The European Accessibility Act (EAA) is an EU directive setting accessibility rules for digital products and services. Learn scope, dates and duties.
- [Evergreen content](https://nodea.io/en/glossary/evergreen-content.md): Evergreen content is timeless material that stays relevant and keeps driving traffic long after publishing. Learn its traits, examples and SEO role.
- [Exact match anchor text](https://nodea.io/en/glossary/exact-match-anchor-text.md): Exact match anchor text is link text that exactly matches the target keyword. Learn its role in SEO, the risks and safe proportions in a link profile.
- [Exploit](https://nodea.io/en/glossary/exploit.md): An exploit is code or a technique that abuses a software vulnerability to seize control of a system. Learn the types, the mechanism and how to defend.
- [Express.js](https://nodea.io/en/glossary/express-js.md): Express.js is a minimalist web framework for Node.js used to build APIs and server apps. Learn about routing, middleware and typical use cases.
- [External linking](https://nodea.io/en/glossary/external-linking.md): External linking means pointing from your site to other domains. Learn its SEO role, outbound link attributes and how to link out safely to good sources.
- [Eye tracking](https://nodea.io/en/glossary/eye-tracking.md): Eye tracking is technology that measures eye movement, used in UX and usability research. Learn how it works and its practical applications.
- [Facebook Ads](https://nodea.io/en/glossary/facebook-ads.md): Facebook Ads is Meta's advertising platform for running paid campaigns targeted at precisely defined audiences across Facebook, Instagram and Messenger.
- [Facebook Pixel](https://nodea.io/en/glossary/facebook-pixel.md): The Facebook Pixel (Meta Pixel) is a snippet that tracks on-site conversions. Learn how it works, what it does and how it powers ad campaigns.
- [Faceted Navigation](https://nodea.io/en/glossary/faceted-navigation.md): Faceted navigation lets users filter products by multiple attributes at once. Learn its UX benefits and the SEO risks around crawling and duplicates.
- [Fail2ban](https://nodea.io/en/glossary/fail2ban.md): Fail2ban is a Linux security tool that scans log files and automatically bans IP addresses running brute-force attacks and service scans. See how it works.
- [Favicon](https://nodea.io/en/glossary/favicon.md): A favicon is the small icon that identifies a website in browser tabs, bookmarks and mobile search results. Learn how to add one and which formats to use.
- [FCP (First Contentful Paint)](https://nodea.io/en/glossary/fcp.md): FCP (First Contentful Paint) measures the time until the first piece of page content is rendered. Learn how it works and how to improve the metric.
- [Feature toggle](https://nodea.io/en/glossary/feature-toggle.md): A feature toggle (feature flag) turns application features on or off at runtime, without deploying new code. Learn the flag types and their common uses.
- [Featured snippets](https://nodea.io/en/glossary/featured-snippets.md): Featured snippets are highlighted answer boxes shown at the top of Google results. Learn how they work and how to win the coveted position zero.
- [FID (First Input Delay)](https://nodea.io/en/glossary/fid.md): FID (First Input Delay) measured the delay before a page responded to the very first user interaction. Learn how it worked and what metric replaced it.
- [Firewall](https://nodea.io/en/glossary/firewall.md): A firewall filters traffic between a network and a server using rules, blocking unwanted connections. Learn the types and uses of firewalls.
- [Flask](https://nodea.io/en/glossary/flask.md): Flask is a lightweight web microframework for Python used to build web apps and APIs. Learn how it works, its advantages and its typical use cases.
- [Floodlight](https://nodea.io/en/glossary/floodlight.md): Floodlight is Google Marketing Platform's conversion tracking technology, measuring user actions after they interact with an ad. Learn how it works.
- [Flynax](https://nodea.io/en/glossary/flynax.md): Flynax is a commercial PHP script for building classified-ads sites and directories. Learn its features, architecture and hosting requirements.
- [Framework](https://nodea.io/en/glossary/framework.md): A framework is a ready programming skeleton that imposes structure and provides components for building applications. Learn the types and benefits.
- [Freeware](https://nodea.io/en/glossary/freeware.md): Freeware is software distributed free of charge but usually without access to the source code. See how it differs from open source and shareware.
- [Fresh site bonus](https://nodea.io/en/glossary/fresh-site-bonus.md): Fresh site bonus is the observed temporary visibility boost a new site gets in Google right after indexing. Learn how it works and how to use it.
- [Friendly URL](https://nodea.io/en/glossary/friendly-url.md): A friendly URL is a readable link built from words instead of parameters. Learn its SEO and UX benefits and how URL rewriting implements clean addresses.
- [Frontend](https://nodea.io/en/glossary/frontend.md): Frontend is the part of a web app that runs in the browser. Learn the core HTML, CSS and JavaScript stack and how it differs from the backend.
- [FTP](https://nodea.io/en/glossary/ftp.md): FTP is a protocol for transferring files between a computer and a server. Learn active and passive modes and why SFTP and FTPS are safer alternatives.
- [FuelPHP](https://nodea.io/en/glossary/fuelphp.md): FuelPHP is a lightweight PHP framework built on the MVC and HMVC patterns. Learn its architecture, key features and place among modern PHP frameworks.
- [GDN (Google Display Network)](https://nodea.io/en/glossary/google-display-network.md): GDN is Google's ad network spanning millions of sites, apps and YouTube. Learn display ad formats, targeting options and how GDN fits into ad campaigns.
- [GDPR](https://nodea.io/en/glossary/gdpr.md): GDPR is the EU regulation on personal data protection. Learn its core principles, the rights it grants users and the duties it places on companies.
- [Geotargeting](https://nodea.io/en/glossary/geotargeting.md): Geotargeting delivers content and ads based on a user's location. Learn how location is detected and how geotargeting is used in advertising and local SEO.
- [Git](https://nodea.io/en/glossary/git.md): Git is a distributed version control system that tracks code changes. Learn commits, branches and repositories and how Git powers teamwork and DevOps.
- [GitHub](https://nodea.io/en/glossary/github.md): GitHub hosts Git repositories with tools for code collaboration. Learn about pull requests, GitHub Actions and how GitHub differs from Git itself.
- [GitOps](https://nodea.io/en/glossary/gitops.md): GitOps manages infrastructure with a Git repository as the single source of truth. Learn the declarative principle and how automatic reconciliation works.
- [Glue records](https://nodea.io/en/glossary/glue-records.md): Glue records are DNS entries that tie a nameserver to its IP in the parent zone. Learn the circular dependency problem and custom nameserver setup.
- [Google Ads](https://nodea.io/en/glossary/google-ads.md): Google Ads is Google's auction-based advertising system. Learn campaign types, the cost-per-click model and how ad ranking works in search results.
- [Google Analytics](https://nodea.io/en/glossary/google-analytics.md): Google Analytics is a tool for analysing website traffic. Learn the GA4 event model, key metrics and how the data drives marketing decisions.
- [Google Assistant](https://nodea.io/en/glossary/google-assistant.md): Google Assistant is Google's voice-driven virtual assistant. See how it parses speech, where its answers come from, and what voice search means for SEO.
- [Google Business Profile (Google My Business)](https://nodea.io/en/glossary/google-business-profile.md): A Google Business Profile (formerly Google My Business) is a free business listing in Search and Maps. Learn how it works and how it supports local SEO.
- [Google Knowledge Panel](https://nodea.io/en/glossary/google-knowledge-panel.md): The Google Knowledge Panel is an info box in search results about a person, brand or place. Learn its data sources, the Knowledge Graph and how to get one.
- [Google Merchant Center](https://nodea.io/en/glossary/google-merchant-center.md): Google Merchant Center manages product data for Shopping ads. Learn about the product feed, integration with Google Ads and its role in e-commerce.
- [Google penalty](https://nodea.io/en/glossary/google-penalty.md): A Google penalty is an algorithmic or manual sanction that lowers a site's rankings for breaking the guidelines. Learn the types and how to avoid them.
- [Google Search Console](https://nodea.io/en/glossary/google-search-console.md): Google Search Console monitors a site's visibility in Google. Learn about performance, indexing and Core Web Vitals reports and how SEO teams use them.
- [Google Spam Update](https://nodea.io/en/glossary/google-spam-update.md): A Google Spam Update targets spam in search results. Learn about the SpamBrain system, the types of violations it catches and how to protect your site.
- [Googlebot](https://nodea.io/en/glossary/googlebot.md): Googlebot is Google's crawler that fetches pages for the search index. Learn how crawling, rendering and crawl budget work, and how to control the bot.
- [Grafana](https://nodea.io/en/glossary/grafana.md): Grafana is an open-source platform for visualizing metrics on interactive dashboards. Learn data sources, panels, alerting and Prometheus integration.
- [Grav CMS](https://nodea.io/en/glossary/grav-cms.md): Grav CMS is a flat-file, database-free content management system built on Markdown files. Learn how it works, its benefits and common use cases.
- [Grey hat SEO](https://nodea.io/en/glossary/grey-hat-seo.md): Grey hat SEO sits between allowed and forbidden Google practices. Learn examples, the risks involved and how it differs from white hat and black hat SEO.
- [Growth hacking](https://nodea.io/en/glossary/growth-hacking.md): Growth hacking is a rapid-growth method built on data and experiments. Learn the test cycle, the AARRR funnel and example tactics used by startups.
- [GTmetrix](https://nodea.io/en/glossary/gtmetrix.md): GTmetrix is a tool for measuring website speed and performance. Learn its metrics, Core Web Vitals scoring and how to read the report to speed up a site.
- [Gzip](https://nodea.io/en/glossary/gzip.md): Gzip is a data compression method for HTTP that shrinks file size and speeds up pages. Learn how it works and how to enable it in your server config.
- [Hamburger menu](https://nodea.io/en/glossary/hamburger-menu.md): A hamburger menu is a three-line icon that reveals hidden navigation, mainly on mobile. Learn how it works and the UX pros and cons of the pattern.
- [Hard bounce](https://nodea.io/en/glossary/hard-bounce.md): A hard bounce is a permanent email rejection caused by an invalid address. Learn the causes, the soft bounce difference and its deliverability impact.
- [Hashtag](https://nodea.io/en/glossary/hashtag.md): A hashtag is a word preceded by # that groups content around a topic on social media. Learn how it works, its types and best practices for using it.
- [HDD (Hard Disk Drive)](https://nodea.io/en/glossary/hdd-drive.md): An HDD stores data magnetically on spinning platters, offering huge capacity at a low price per GB. Learn how hard drives work and when to pick HDD over SSD.
- [Headless e-commerce](https://nodea.io/en/glossary/headless-ecommerce.md): Headless e-commerce decouples the storefront from the commerce backend via an API. Learn the architecture, its pros, cons and typical use cases.
- [High availability (HA)](https://nodea.io/en/glossary/high-availability.md): High availability (HA) designs systems to survive failures. Learn about redundancy, failover, clustering and the availability nines that measure uptime.
- [Hosting](https://nodea.io/en/glossary/hosting.md): Web hosting provides server space and resources that keep a website online. Learn the types — shared, VPS, dedicated and cloud — and where each one fits.
- [Hreflang](https://nodea.io/en/glossary/hreflang.md): The hreflang attribute tells search engines which language and region a page targets. Learn the syntax, self-referencing, x-default and common mistakes.
- [HSTS (HTTP Strict Transport Security)](https://nodea.io/en/glossary/hsts.md): HSTS forces HTTPS connections and defends against downgrade and SSL stripping attacks. Learn the header, its directives, preload lists and safe rollout.
- [HTML](https://nodea.io/en/glossary/html.md): HTML is the markup language describing the structure of web pages. Learn about tags, semantics, HTML5 and how it relates to CSS, JavaScript and SEO.
- [HTML Headings (H1–H6)](https://nodea.io/en/glossary/html-headings-h1-h6.md): HTML headings H1–H6 build a page's content hierarchy. Learn how they shape SEO, accessibility and readability, and how to structure them correctly.
- [HTTP](https://nodea.io/en/glossary/http.md): HTTP is the protocol browsers use to talk to web servers. Learn its methods, status codes and headers, plus how HTTP differs from encrypted HTTPS.
- [HTTP/2](https://nodea.io/en/glossary/http-2.md): HTTP/2 speeds up page loads with multiplexing, header compression and prioritization. Learn how it differs from HTTP/1.1 and why it needs HTTPS.
- [HTTP/3](https://nodea.io/en/glossary/http-3.md): HTTP/3 runs on QUIC over UDP, removing transport head-of-line blocking and speeding up connections. Learn how it differs from HTTP/2 and the role of TLS.
- [HTTPS](https://nodea.io/en/glossary/https.md): HTTPS is the encrypted version of HTTP built on TLS. Learn the role of the SSL certificate, the handshake, and how HTTPS affects security, trust and SEO.
- [Hybrid cloud](https://nodea.io/en/glossary/hybrid-cloud.md): Hybrid cloud unites private infrastructure and public cloud into one managed environment. Learn how it works, when it pays off and what it demands.
- [IaaS (Infrastructure as a Service)](https://nodea.io/en/glossary/iaas.md): IaaS is a cloud model delivering virtual servers, networking and storage on demand. Learn the responsibility split and how it differs from PaaS and SaaS.
- [IaC (Infrastructure as Code)](https://nodea.io/en/glossary/iac.md): IaC manages infrastructure through code instead of manual configuration. Learn the declarative approach, idempotency, tooling and its benefits for DevOps.
- [Immutable backup](https://nodea.io/en/glossary/immutable-backup.md): An immutable backup cannot be altered or deleted for a set period. Learn the WORM model, ransomware protection and the 3-2-1-1-0 backup rule.
- [In-stream ads](https://nodea.io/en/glossary/in-stream-ads.md): In-stream ads are video spots shown before, during or after video content. Learn skippable and non-skippable formats and how they are billed.
- [Incognito mode](https://nodea.io/en/glossary/incognito-mode.md): Incognito mode is a private browsing window that doesn't save history, cookies or form data locally. See what it really hides and what it does not.
- [Influencer marketing](https://nodea.io/en/glossary/influencer-marketing.md): Influencer marketing promotes a brand through creators with engaged audiences. Learn influencer tiers, collaboration models, ROI and disclosure rules.
- [Infographic](https://nodea.io/en/glossary/infographic.md): An infographic presents data and information visually. Learn the types of infographics, design principles and their role in content marketing and SEO.
- [INP (Interaction to Next Paint)](https://nodea.io/en/glossary/inp.md): INP (Interaction to Next Paint) is a Core Web Vitals metric measuring page responsiveness to interactions. Learn the INP thresholds and how to improve it.
- [Instagram](https://nodea.io/en/glossary/instagram.md): Instagram is a visual social platform built around photos and video. Learn its content formats, algorithm and role in brand marketing on Instagram.
- [Instagram Story](https://nodea.io/en/glossary/instagram-story.md): An Instagram Story is a vertical post that disappears after 24 hours. Learn the formats, interactive features and marketing uses of Instagram Stories.
- [Installatron](https://nodea.io/en/glossary/installatron.md): Installatron is a hosting auto-installer. Learn about one-click WordPress installs, automatic updates and backups managed straight from your control panel.
- [Integration testing](https://nodea.io/en/glossary/integration-testing.md): Integration testing checks that separate modules work correctly together, not just in isolation. See where it sits between unit and end-to-end tests.
- [Interface](https://nodea.io/en/glossary/interface.md): An interface is a point of contact enabling communication between systems or between humans and machines. Learn about UI, API, CLI and GUI interfaces.
- [Internal linking](https://nodea.io/en/glossary/internal-linking.md): Internal linking connects pages within the same website. Learn its role in SEO, how it distributes link equity and the rules of a solid linking structure.
- [Intranet](https://nodea.io/en/glossary/intranet.md): An intranet is a private network built on internet technologies but limited to one organisation. Learn its uses and how it differs from the open internet.
- [IoT (Internet of Things)](https://nodea.io/en/glossary/iot-internet-of-things.md): IoT (Internet of Things) is a network of devices that connect online and exchange data. Learn how the internet of things works and where it is used.
- [IP Address](https://nodea.io/en/glossary/ip-address.md): An IP address is a unique number that identifies a device on a network using the Internet Protocol. Learn how it works and how IPv4 differs from IPv6.
- [IPv4 Address](https://nodea.io/en/glossary/ipv4-address.md): An IPv4 address is a 32-bit identifier for a device on a network, written as four numbers from 0 to 255. Learn its structure and the role of NAT.
- [IPv6 Address](https://nodea.io/en/glossary/ipv6-address.md): An IPv6 address is a 128-bit next-generation network address in hexadecimal. Learn its structure, advantages over IPv4, and the AAAA record in DNS.
- [Jamstack](https://nodea.io/en/glossary/jamstack.md): Jamstack is a web architecture based on pre-rendering, APIs and JavaScript. Learn the benefits of Jamstack: speed, security and easy scalability.
- [Java](https://nodea.io/en/glossary/java.md): Java is an object-oriented language and platform running on the JVM. Learn the write once, run anywhere principle and where Java is used in practice.
- [JavaScript](https://nodea.io/en/glossary/javascript.md): JavaScript is the programming language behind interactive websites. Learn how JS works in the browser and on the server, plus its practical applications.
- [Jira](https://nodea.io/en/glossary/jira.md): Jira is Atlassian's project management and issue tracking tool for IT teams. Learn about Scrum and Kanban boards and how Jira is used in Agile work.
- [Joomla](https://nodea.io/en/glossary/joomla.md): Joomla is a free, open-source content management system (CMS). Learn Joomla's structure, its capabilities and how it is used to build websites today.
- [JPEG](https://nodea.io/en/glossary/jpeg.md): JPEG is a popular lossy image compression format. Learn how lossy compression works, JPEG's strengths and limits, and its role in page optimisation.
- [jQuery](https://nodea.io/en/glossary/jquery.md): jQuery is a JavaScript library that simplifies DOM manipulation, events and AJAX. Learn how it works, what it's for and whether it's still worth using.
- [JSON](https://nodea.io/en/glossary/json.md): JSON is a lightweight, text-based data interchange format readable by humans and machines. Learn its syntax, data types and role in APIs and configuration.
- [JSON-LD](https://nodea.io/en/glossary/json-ld.md): JSON-LD is Google's recommended format for embedding schema.org structured data. See how it works and how it helps earn rich results in search.
- [JWT](https://nodea.io/en/glossary/jwt.md): JWT is a signed JSON token that carries authentication data between server and client. Learn its structure, benefits and rules for using it securely.
- [Keylogger](https://nodea.io/en/glossary/keylogger.md): A keylogger is software or hardware that records keystrokes to steal passwords and data. Learn the types of keyloggers and how to protect yourself.
- [Keyword](https://nodea.io/en/glossary/keyword.md): A keyword is a term users type into a search engine and around which content is optimised. Learn keyword types, intent and their role in SEO.
- [Keyword cannibalization](https://nodea.io/en/glossary/keyword-cannibalization.md): Keyword cannibalization is when your own pages compete for the same query. Learn how to detect and fix it so you stop losing rankings in Google.
- [Keyword clustering](https://nodea.io/en/glossary/keyword-clustering.md): Keyword clustering groups phrases with a shared intent under one page. See how it builds topical authority and organizes your site's structure.
- [Keyword density](https://nodea.io/en/glossary/keyword-density.md): Keyword density is the percentage share of a phrase in a page's text. Learn how to calculate it and why you shouldn't artificially inflate it.
- [Keyword planner](https://nodea.io/en/glossary/keyword-planner.md): A keyword planner is a tool for researching phrases, their search volume and competition. Learn how it works and how it supports SEO and Google Ads.
- [Keyword stuffing](https://nodea.io/en/glossary/keyword-stuffing.md): Keyword stuffing is cramming keywords into content unnaturally. Learn examples of this black hat SEO tactic and the penalties Google imposes for it.
- [Kibana](https://nodea.io/en/glossary/kibana.md): Kibana visualizes and analyzes data from Elasticsearch. Learn about dashboards, log search and Kibana's role in the ELK stack and monitoring.
- [Knowledge Graph](https://nodea.io/en/glossary/knowledge-graph.md): The Knowledge Graph is Google's knowledge base linking entities and their relationships. Learn how it powers knowledge panels and shapes search and SEO.
- [KPI](https://nodea.io/en/glossary/kpi.md): A KPI is a key performance indicator measuring progress toward business goals. Learn KPI types, the SMART rule and examples across marketing and IT.
- [Kubernetes](https://nodea.io/en/glossary/kubernetes.md): Kubernetes (K8s) is a platform for orchestrating containers that automates deploying and scaling applications. Learn the K8s architecture and its uses.
- [Landing page](https://nodea.io/en/glossary/landing-page.md): A landing page is a standalone page built around a single conversion goal. Learn what makes a landing page effective and its role in advertising campaigns.
- [Laravel](https://nodea.io/en/glossary/laravel.md): Laravel is a popular PHP framework for building web applications. Learn about its MVC architecture, Eloquent ORM, tooling ecosystem and practical uses.
- [Layout](https://nodea.io/en/glossary/layout.md): A layout is how elements are arranged on a web page. Learn layout types, CSS Grid and Flexbox techniques and the principles of responsive design.
- [Lazy loading](https://nodea.io/en/glossary/lazy-loading.md): Lazy loading defers loading resources until they are actually needed. Learn how lazy loading of images works and its impact on page performance.
- [LCP (Largest Contentful Paint)](https://nodea.io/en/glossary/lcp.md): LCP (Largest Contentful Paint) measures how fast a page's largest element renders. Learn the target thresholds and how to optimize your LCP score.
- [Lead magnet](https://nodea.io/en/glossary/lead-magnet.md): A lead magnet is a free resource offered in exchange for contact details. Learn the types of lead magnets and their role in acquiring customers.
- [LESS](https://nodea.io/en/glossary/less.md): LESS is a CSS preprocessor that adds variables, nesting and functions to stylesheets. Learn how LESS works and how it compares with the Sass preprocessor.
- [Let's Encrypt (SSL certificates)](https://nodea.io/en/glossary/lets-encrypt-ssl-certificates.md): Let's Encrypt is a free certificate authority issuing SSL/TLS certificates. Learn how the ACME protocol works and how certificates renew automatically.
- [Lighthouse](https://nodea.io/en/glossary/lighthouse.md): Lighthouse is Google's tool for auditing site performance, accessibility and SEO. Learn its scoring categories and its role in optimizing a website.
- [Link building](https://nodea.io/en/glossary/link-building.md): Link building is the process of earning backlinks to a site. Learn the main tactics, how link quality is judged and how to build a safe backlink profile.
- [Link exchange system (SWL)](https://nodea.io/en/glossary/link-exchange-system.md): A link exchange system automatically places links between member sites to inflate backlink counts. Learn how it works and the SEO risk it poses from Google.
- [Link gap](https://nodea.io/en/glossary/link-gap.md): A link gap is the set of domains linking to competitors but not to you. Learn how link gap analysis surfaces ready-made backlink targets for your SEO.
- [Link juice](https://nodea.io/en/glossary/link-juice.md): Link juice is the informal term for SEO value a link passes to its target. Learn how it flows, the role of nofollow and how to manage it across a site.
- [Link profile](https://nodea.io/en/glossary/link-profile.md): A link profile is the full set of links pointing to a site, along with their quality and diversity. Learn how it affects SEO and how to analyse it.
- [Linting](https://nodea.io/en/glossary/linting.md): Linting is automated analysis of code for errors and style issues. Learn about popular linters, their role in CI/CD and how they differ from a formatter.
- [LiteSpeed](https://nodea.io/en/glossary/litespeed.md): LiteSpeed is a high-performance web server compatible with Apache, with built-in caching and HTTP/3. Learn its benefits, LSCache and how it compares.
- [LLM](https://nodea.io/en/glossary/llm.md): An LLM is a large language model trained on vast text corpora. Learn how transformers work, what LLMs are used for and their role in AI and modern search.
- [llms.txt](https://nodea.io/en/glossary/llms-txt.md): llms.txt is a Markdown file that points AI models to a site's key content. Learn its structure, purpose and how it differs from the robots.txt standard.
- [Load balancer](https://nodea.io/en/glossary/load-balancer.md): A load balancer distributes network traffic across multiple servers to boost performance and availability. Learn balancing algorithms and L4 vs L7 layers.
- [Local File Inclusion](https://nodea.io/en/glossary/local-file-inclusion.md): Local File Inclusion (LFI) is a flaw that lets an attacker include a server's local files via parameter manipulation. Learn the attack and how to defend.
- [Local SEO](https://nodea.io/en/glossary/local-seo.md): Local SEO optimizes a business's visibility for location-based searches. Learn the role of Google Business Profile, NAP citations and customer reviews.
- [Location Extension](https://nodea.io/en/glossary/location-extension.md): A Google Ads location extension shows your business address next to an ad. Learn how it works, its link to Business Profile and its local-traffic benefits.
- [Long tail](https://nodea.io/en/glossary/long-tail.md): Long tail keywords are longer, specific search phrases with low volume but high intent. Learn how the long tail drives traffic and wins in SEO.
- [Magento](https://nodea.io/en/glossary/magento.md): Magento is a powerful open-source e-commerce platform (Adobe Commerce). Learn its architecture, server requirements and where it fits for large stores.
- [Mailing list](https://nodea.io/en/glossary/mailing-list.md): A mailing list is a permission-based collection of subscriber email addresses. Learn to grow it legally, segment it and keep it clean for deliverability.
- [Majestic SEO](https://nodea.io/en/glossary/majestic-seo.md): Majestic SEO is a backlink analysis tool built on its own web index. Learn about its Trust Flow and Citation Flow metrics for link building.
- [Man in the middle](https://nodea.io/en/glossary/man-in-the-middle.md): A man in the middle (MITM) attack intercepts communication between two parties. Learn how MITM works and how TLS, HTTPS and HSTS protect against it.
- [Managed Server](https://nodea.io/en/glossary/managed-server.md): A managed server is a service where the provider handles OS administration, updates, security and monitoring. See how it differs from an unmanaged server.
- [MariaDB](https://nodea.io/en/glossary/mariadb.md): MariaDB is an open-source relational database and a fork of MySQL. Learn its architecture, storage engines, MySQL compatibility and role in hosting.
- [Media query](https://nodea.io/en/glossary/media-query.md): A media query is a CSS rule that adapts styles to device properties. Learn media query syntax, breakpoints and their role in responsive web design.
- [Memcached](https://nodea.io/en/glossary/memcached.md): Memcached is a fast in-memory caching system storing key-value data in RAM. Learn how it works and how Memcached compares to Redis in hosting environments.
- [memory\_limit](https://nodea.io/en/glossary/memory-limit.md): memory\_limit is a PHP directive that sets the maximum RAM a single script may use. Learn how it works, typical values and how to change the limit.
- [Meta description](https://nodea.io/en/glossary/meta-description.md): The meta description is the page summary shown in search results. Learn its optimal length, impact on CTR and how to write effective meta descriptions.
- [Meta robots](https://nodea.io/en/glossary/meta-robots.md): The meta robots tag tells search engine crawlers whether to index a page and follow its links. Learn the index, noindex, follow and nofollow directives.
- [Micro-conversion](https://nodea.io/en/glossary/micro-conversion.md): A micro-conversion is a small action that moves a user toward the main goal. Learn examples, how it differs from macro-conversions and its role.
- [Middleware](https://nodea.io/en/glossary/middleware.md): Middleware is software that sits between components of a system. Learn the role of middleware in web apps, frameworks and processing HTTP requests.
- [MLOps](https://nodea.io/en/glossary/mlops.md): MLOps is a set of practices that automate the machine learning lifecycle — from data and training to deployment and monitoring. See how it works.
- [Mobile-first indexing](https://nodea.io/en/glossary/mobile-first-indexing.md): Mobile-first indexing is how Google crawls and ranks pages using their mobile version. Learn the rules, SEO consequences and best practices.
- [Mockup](https://nodea.io/en/glossary/mockup.md): A mockup is a high-fidelity static design showing the final look of an interface or graphic. Learn how it differs from a wireframe and a prototype.
- [ModSecurity](https://nodea.io/en/glossary/modsecurity.md): ModSecurity is an open-source web application firewall (WAF) for Apache and Nginx that filters HTTP traffic by rules. Learn how it works and the OWASP CRS.
- [MODX](https://nodea.io/en/glossary/modx.md): MODX is an open-source PHP CMS and content framework prized for full control over HTML output and strong security. See its templates and uses.
- [MongoDB](https://nodea.io/en/glossary/mongodb.md): MongoDB is a document-oriented NoSQL database storing data in flexible BSON documents. Learn its data model, sharding, replication and typical use cases.
- [Moodle](https://nodea.io/en/glossary/moodle.md): Moodle is an open-source e-learning platform (LMS) for building online courses. Learn its features, PHP and MySQL architecture, and hosting requirements.
- [MozRank](https://nodea.io/en/glossary/mozrank.md): MozRank is a historic Moz metric scoring a page's link popularity from 0 to 10, inspired by PageRank. Learn how it works and its role in SEO today.
- [MozTrust](https://nodea.io/en/glossary/moztrust.md): MozTrust is a Moz metric scoring a page's trust based on its link distance from trusted seed sites. Learn how it differs from MozRank and its role in SEO.
- [MTA-STS](https://nodea.io/en/glossary/mta-sts.md): MTA-STS is a standard that enforces encrypted TLS connections between mail servers, protecting against downgrade attacks. Learn its policy and DNS records.
- [Multimodality](https://nodea.io/en/glossary/multimodality.md): Multimodality is an AI model's ability to process multiple data types at once — text, image, audio and video. Learn how it works and where it's applied.
- [MVP](https://nodea.io/en/glossary/mvp.md): An MVP (Minimum Viable Product) is the simplest version of a product with core features, letting you test an idea on the market fast. Learn the concept.
- [MX record](https://nodea.io/en/glossary/mx-record.md): An MX record names the mail servers that accept email for a domain. Learn the role of priorities, links to SPF/DKIM/DMARC and email configuration.
- [MyBB](https://nodea.io/en/glossary/mybb.md): MyBB is free, open-source forum software written in PHP and MySQL. Learn its features, architecture and the hosting requirements of a discussion forum.
- [MySQL](https://nodea.io/en/glossary/mysql.md): MySQL is a popular relational SQL database powering most web applications. Learn about tables, SQL queries, storage engines like InnoDB, indexes and more.
- [n8n](https://nodea.io/en/glossary/n8n.md): n8n is an open-source workflow automation tool that connects apps and APIs into visual workflows. Learn about nodes, self-hosting and common use cases.
- [Negative SEO](https://nodea.io/en/glossary/negative-seo.md): Negative SEO means deliberate attempts to push a competitor's site down in Google. Learn common attack methods and how to protect your rankings.
- [Netiquette](https://nodea.io/en/glossary/netiquette.md): Netiquette is the set of etiquette rules for polite online conduct — in email, forums and social media. Learn the core principles of good communication.
- [Next.js](https://nodea.io/en/glossary/next-js.md): Next.js is a React framework for building apps with server-side rendering and static generation. Learn SSR, the App Router and its SEO benefits.
- [Nginx](https://nodea.io/en/glossary/nginx.md): Nginx is a high-performance web server, reverse proxy and load balancer built on an event-driven model. See how it beats Apache under heavy load.
- [NLP (Natural Language Processing)](https://nodea.io/en/glossary/nlp.md): NLP is the AI field focused on understanding and generating human language. Learn its uses in search engines, chatbots and SEO content analysis.
- [No-code](https://nodea.io/en/glossary/no-code.md): No-code means building apps and sites without coding, using visual editors. Learn the benefits, limitations and how it differs from the low-code approach.
- [Node.js](https://nodea.io/en/glossary/node-js.md): Node.js is a server-side JavaScript runtime. Learn its non-blocking model, the event loop and its uses in APIs and real-time web applications today.
- [Nofollow attribute](https://nodea.io/en/glossary/nofollow-attribute.md): The nofollow attribute tells search engines not to pass ranking power through a link. Learn its uses, the sponsored and ugc variants, and its SEO impact.
- [Noindex](https://nodea.io/en/glossary/noindex.md): The noindex directive keeps a page out of search results. Learn its syntax, the difference from robots.txt and typical use cases for excluding pages.
- [NoSQL](https://nodea.io/en/glossary/nosql.md): NoSQL refers to non-relational databases — document, key-value, graph. Learn the types, differences from SQL and their use in big data and scaling.
- [npm](https://nodea.io/en/glossary/npm.md): npm is the package manager for Node.js and the largest JavaScript library registry. Learn about package.json, dependencies and how npm and yarn compare.
- [NPS (Net Promoter Score)](https://nodea.io/en/glossary/nps.md): NPS is a customer loyalty metric measuring willingness to recommend a brand. Learn the 0–10 scale, the promoter/detractor split and how to score it.
- [NS record](https://nodea.io/en/glossary/ns-record.md): An NS record names the authoritative name servers for a domain and delegates its DNS zone. Learn its role, delegation and its link to glue records.
- [Nuxt.js](https://nodea.io/en/glossary/nuxt-js.md): Nuxt.js is a Vue-based framework for building apps with SSR and static generation. Learn its SEO benefits, file-based routing and rendering modes.
- [NVMe](https://nodea.io/en/glossary/nvme.md): NVMe is a storage protocol for SSDs over the PCIe bus, delivering far higher performance than SATA. Learn the differences and its uses in hosting and VPS.
- [OAuth](https://nodea.io/en/glossary/oauth.md): OAuth is an open authorization standard granting apps access to data without your password. Learn about tokens, flows and how it differs from OpenID.
- [Object storage](https://nodea.io/en/glossary/object-storage.md): Object storage keeps data as objects with metadata in a flat namespace, accessed over an HTTP API. Learn how it differs from block and file storage.
- [Observability](https://nodea.io/en/glossary/observability.md): Observability is the ability to understand a system's internal state from the data it emits: logs, metrics and traces. See the three pillars explained.
- [OCSP stapling](https://nodea.io/en/glossary/ocsp-stapling.md): OCSP stapling lets a web server attach a signed proof of a TLS certificate's validity to the handshake. Learn how it speeds pages and protects privacy.
- [OctoberCMS 2](https://nodea.io/en/glossary/octobercms-2.md): OctoberCMS 2 is a developer-focused content management system built on the Laravel framework. Learn its architecture, plugins and hosting requirements.
- [Off-page SEO](https://nodea.io/en/glossary/off-page-seo.md): Off-page SEO is the work done beyond your site to build its authority: link building, mentions, digital PR and social signals. See how it works.
- [On-page SEO](https://nodea.io/en/glossary/on-page-seo.md): On-page SEO optimizes elements on the page itself: content, headings, meta tags and speed. Learn the ranking factors you control completely.
- [OPcache](https://nodea.io/en/glossary/opcache.md): OPcache is PHP's built-in bytecode accelerator that caches compiled opcode in shared memory. Learn how it works and how it speeds up any PHP website.
- [Open Graph](https://nodea.io/en/glossary/open-graph.md): Open Graph is a meta-tag protocol that controls how shared links look on social media. Learn about og:title, og:image and how to use them in practice.
- [Open rate](https://nodea.io/en/glossary/open-rate.md): Open rate is the percentage of delivered emails that recipients opened. Learn the formula, the factors behind it and how privacy features skew it.
- [OpenCart](https://nodea.io/en/glossary/opencart.md): OpenCart is a free, open-source online store platform built on PHP and MySQL. Learn its features, extensions and typical hosting requirements.
- [Optimization](https://nodea.io/en/glossary/optimization.md): Optimization is the process of improving performance and efficiency — from page load speed to server resource use. Learn the areas and techniques.
- [Organic search results](https://nodea.io/en/glossary/organic-search-results.md): Organic search results are the unpaid SERP listings an algorithm ranks purely on relevance and quality. Learn how they differ from paid results.
- [Orphan page](https://nodea.io/en/glossary/orphan-page.md): An orphan page is a page with no internal links pointing to it, so crawlers and users can't reach it through navigation. Learn the SEO impact and the fix.
- [osCommerce](https://nodea.io/en/glossary/oscommerce.md): osCommerce is one of the earliest open-source online store platforms built on PHP and MySQL. Learn its history, features and hosting requirements.
- [Out-stream ads](https://nodea.io/en/glossary/out-stream-ads.md): Out-stream ads are video spots shown outside of any video — inside articles, sites and apps. Learn how they work and how they differ from in-stream.
- [Outbound marketing](https://nodea.io/en/glossary/outbound-marketing.md): Outbound marketing is a model where a brand actively pushes its message to the audience: ads, cold email, telemarketing. See how it differs from inbound.
- [OWASP](https://nodea.io/en/glossary/owasp.md): OWASP is a nonprofit that publishes open application-security standards. Learn about the OWASP Top 10, ASVS and how its rules shape secure hosting.
- [PaaS](https://nodea.io/en/glossary/paas.md): PaaS is a cloud model where the provider delivers a ready application runtime. Learn how PaaS differs from IaaS and SaaS and where it fits best.
- [Page Experience](https://nodea.io/en/glossary/page-experience.md): Page Experience is a set of Google signals measuring how comfortable a page feels. Learn about Core Web Vitals, HTTPS, mobile-friendliness and SEO impact.
- [Page indexing](https://nodea.io/en/glossary/page-indexing.md): Page indexing is how a search engine adds pages to its database. Learn how crawling differs from indexing and the role of sitemaps, robots.txt and noindex.
- [PageRank](https://nodea.io/en/glossary/pagerank.md): PageRank is Google's algorithm that scores a page's importance from its links. Learn how it works, its SEO impact and its link to backlink profiles.
- [PageSpeed](https://nodea.io/en/glossary/pagespeed.md): PageSpeed means page load speed and Google's PageSpeed Insights tool. Learn how the score, Core Web Vitals and optimizations make a site faster.
- [Pagination](https://nodea.io/en/glossary/pagination.md): Pagination splits long content lists into separate numbered pages. Learn how it works, its SEO impact and how it differs from infinite scroll.
- [Paid search results](https://nodea.io/en/glossary/paid-search-results.md): Paid search results are ads in the SERP labeled Sponsored. Learn how they work, how they differ from organic results and how they are billed.
- [Partial Match Anchor Text](https://nodea.io/en/glossary/partial-match-anchor-text.md): Partial match anchor text is link text containing part of a target keyword. Learn how it differs from exact match and its safe role in a link profile.
- [Password](https://nodea.io/en/glossary/password.md): A password is a secret string that confirms a user's identity. Learn how to create strong passwords, how they are stored securely and common threats.
- [Pay Per Sale (PPS)](https://nodea.io/en/glossary/pay-per-sale-pps.md): Pay Per Sale (PPS) is a pricing model where commission is paid only for a completed sale. Learn how it works and how it differs from CPC and CPL.
- [Penetration testing](https://nodea.io/en/glossary/penetration-testing.md): A penetration test is a controlled attack on a system to find and exploit real vulnerabilities. Learn pentest types (black/white/grey box), stages and OWASP.
- [People Also Ask](https://nodea.io/en/glossary/people-also-ask.md): People Also Ask is a block of related questions in Google results. Learn how it works, its impact on CTR and how to optimize content to appear in PAA.
- [Performance Max](https://nodea.io/en/glossary/performance-max.md): Performance Max is a Google Ads campaign type serving ads across all channels with AI automation. Learn how it works, its assets and its use cases.
- [Performance testing](https://nodea.io/en/glossary/performance-testing.md): Performance testing measures a system's speed and stability under load. Learn load, stress and spike tests, key metrics and tools like JMeter and k6.
- [Phalcon](https://nodea.io/en/glossary/phalcon.md): Phalcon is a high-performance PHP framework delivered as a C extension. Learn how it works, its MVC architecture and its hosting requirements.
- [Phishing](https://nodea.io/en/glossary/phishing.md): Phishing is a scam that impersonates a trusted institution to steal data. Learn how the attack works, common examples and how to protect against it.
- [Phoenix](https://nodea.io/en/glossary/phoenix.md): Phoenix is an Elixir web framework known for performance, concurrency and LiveView. Learn how it works, real-time applications and where it fits best.
- [PHP](https://nodea.io/en/glossary/php.md): PHP is a server-side scripting language powering most of the web, including WordPress. Learn how it works, its versions, frameworks and hosting.
- [PHP 5.0](https://nodea.io/en/glossary/php-5-0.md): PHP 5.0 was a landmark 2004 PHP release with the Zend Engine 2 and a mature object model. Learn its significance and its end-of-life support status.
- [PHP 5.1](https://nodea.io/en/glossary/php-5-1.md): PHP 5.1 is a 2005 release of the PHP language that introduced the PDO database layer and a faster engine. Learn its key changes, support status and impact.
- [PHP 5.2](https://nodea.io/en/glossary/php-5-2.md): PHP 5.2 is a 2006 PHP release that added native JSON support and the filter extension. Learn its key changes, support status and impact on hosting.
- [PHP 5.3](https://nodea.io/en/glossary/php-5-3.md): PHP 5.3 is a landmark 2009 release that introduced namespaces, anonymous functions and late static binding. Learn its key changes and why it mattered.
- [PHP 5.4](https://nodea.io/en/glossary/php-5-4.md): PHP 5.4 is a 2012 release that introduced traits, the short array syntax and a built-in development server. Learn its key changes and support status.
- [PHP 5.5](https://nodea.io/en/glossary/php-5-5.md): PHP 5.5 is a 2013 release that bundled OPcache, added generators and a new password API. Learn its key changes, support status and impact on performance.
- [PHP 5.6](https://nodea.io/en/glossary/php-5-6.md): PHP 5.6 is the final 5.x release, from 2014. It added constant expressions and the ... operator. Learn its key changes, end of life and the move to PHP 7.
- [PHP 7.0](https://nodea.io/en/glossary/php-7-0.md): PHP 7.0 is a 2015 release whose new engine roughly doubled performance. Learn about scalar type declarations, return types and why this version mattered.
- [PHP 7.1](https://nodea.io/en/glossary/php-7-1.md): PHP 7.1 is a 2016 release that added nullable types, the void return type and class-constant visibility. Learn its key changes and support status.
- [PHP 7.2](https://nodea.io/en/glossary/php-7-2.md): PHP 7.2 is a 2017 release that added the object type and modern Sodium cryptography. Learn its key changes, support status and impact on security.
- [PHP 7.3](https://nodea.io/en/glossary/php-7-3.md): PHP 7.3 is a 2018 release that added flexible heredoc and trailing commas in calls. Learn its key changes, support status and why the version mattered.
- [PHP 7.4](https://nodea.io/en/glossary/php-7-4.md): PHP 7.4 is the final 7.x release, from 2019. It added typed properties, arrow functions and preloading. Learn its key changes and end of life.
- [PHP 8.0](https://nodea.io/en/glossary/php-8-0.md): PHP 8.0 is a 2020 release that introduced the JIT compiler, attributes and named arguments. Learn its key changes, performance gains and why it mattered.
- [PHP 8.1](https://nodea.io/en/glossary/php-8-1.md): PHP 8.1 is a 2021 release that introduced enums, fibers and readonly properties. Learn its key changes, support status and why the version mattered.
- [PHP 8.2](https://nodea.io/en/glossary/php-8-2.md): PHP 8.2 is a 2022 release that added readonly classes and composite types. Learn its key changes, support status and what it means for applications.
- [PHP 8.4](https://nodea.io/en/glossary/php-8-4.md): PHP 8.4 is a 2024 release that introduced property hooks and asymmetric visibility. Learn its key additions, performance and why this PHP version matters.
- [PHP-FPM](https://nodea.io/en/glossary/php-fpm.md): PHP-FPM is a FastCGI process manager for PHP. Learn how it runs worker pools, speeds up applications and pairs with Nginx and Apache on modern servers.
- [phpBB](https://nodea.io/en/glossary/phpbb.md): phpBB is free, open-source forum software written in PHP. Learn how it works, what it needs to run and where a classic bulletin board still fits today.
- [phpFox](https://nodea.io/en/glossary/phpfox.md): phpFox is a commercial PHP script for building your own social network. Learn how it works, what it offers and the server resources it needs to run.
- [phpinfo](https://nodea.io/en/glossary/phpinfo.md): phpinfo() is a PHP function that prints the full environment configuration. Learn what it reveals, how to use it and why to delete it from production.
- [phpMyAdmin](https://nodea.io/en/glossary/phpmyadmin.md): phpMyAdmin is a web-based tool for managing MySQL and MariaDB databases. Learn how it works, what it does and how to use it securely on any server.
- [Pillar page](https://nodea.io/en/glossary/pillar-page.md): A pillar page is a broad hub article that links related pieces into a topic cluster. Learn how it builds topical authority and supports SEO.
- [Pimcore](https://nodea.io/en/glossary/pimcore.md): Pimcore is an open-source platform combining PIM, DAM, CMS and e-commerce. Learn how it manages product data and what server resources it needs.
- [Ping](https://nodea.io/en/glossary/ping.md): Ping is a network tool that checks host reachability and round-trip time. Learn how the ICMP protocol works and how to read a ping result correctly.
- [Piwik / Matomo](https://nodea.io/en/glossary/piwik-matomo.md): Matomo (formerly Piwik) is open-source web analytics with full data ownership. Learn how it works and how it differs from Google Analytics in practice.
- [Pligg](https://nodea.io/en/glossary/pligg.md): Pligg is an open-source CMS for building Digg-style social news sites. Learn how its community voting system works and what it needs to run.
- [Plugin](https://nodea.io/en/glossary/plugin.md): A plugin extends a program's features without altering its core. Learn how plugin architecture works and where it is used across modern software.
- [PNG](https://nodea.io/en/glossary/png.md): PNG is a lossless image format with transparency support. Learn how PNG compression works and when to choose it over JPEG or WebP in practice.
- [PoC (Proof of Concept)](https://nodea.io/en/glossary/proof-of-concept.md): A PoC (Proof of Concept) is a small project that proves whether an idea is technically feasible. Learn how to plan one and why teams build them.
- [Polyfill](https://nodea.io/en/glossary/polyfill.md): A polyfill is a piece of JavaScript that supplies a missing feature to older browsers. Learn how polyfills work and when it makes sense to use them.
- [Pop-up](https://nodea.io/en/glossary/pop-up.md): A pop-up is a window that appears over a web page to grab attention. Learn the types of pop-ups, their marketing uses and their impact on UX and SEO.
- [Portfolio](https://nodea.io/en/glossary/portfolio.md): A portfolio is a curated collection of a creator's or company's best work that showcases their skills. Learn how to build an effective online portfolio.
- [PostgreSQL](https://nodea.io/en/glossary/postgresql.md): PostgreSQL is an advanced, open-source object-relational SQL database. Learn its capabilities, data types, transactions and typical real-world uses.
- [Presell pages](https://nodea.io/en/glossary/presell-pages.md): Presell pages warm up interest before sending users to an offer. Learn how presell pages work, where they fit in the funnel and how to use them well.
- [PrestaShop](https://nodea.io/en/glossary/prestashop.md): PrestaShop is an open-source e-commerce platform for building online stores. Learn its features, modules, hosting requirements and typical use cases.
- [Product Listing Ads (PLA)](https://nodea.io/en/glossary/product-listing-ads.md): Product Listing Ads (PLA) are Google shopping ads with an image, price and title. Learn how they work, where their data comes from and how they sell.
- [Programmatic SEO](https://nodea.io/en/glossary/programmatic-seo.md): Programmatic SEO generates many pages from a template and data to cover long-tail queries. Learn how it works and how to do it without spam.
- [Prompt](https://nodea.io/en/glossary/prompt.md): A prompt is a command or query sent to an AI model that shapes its response. Learn how prompts work and how to write effective prompts for language models.
- [PTR record](https://nodea.io/en/glossary/ptr-record.md): A PTR record performs reverse DNS: it maps an IP address to a domain name. Learn its role in email deliverability and who can set it.
- [PUP](https://nodea.io/en/glossary/pup-potentially-unwanted-program.md): A PUP (Potentially Unwanted Program) installs alongside other software and toes the line of malware. Learn the common types, risks and how to remove them.
- [PuTTY](https://nodea.io/en/glossary/putty.md): PuTTY is a free SSH and Telnet client for Windows used to manage servers remotely. Learn how to configure connections, use SSH keys and the bundled tools.
- [PWA](https://nodea.io/en/glossary/pwa-progressive-web-app.md): A PWA (Progressive Web App) is a web app that behaves like a native one: installable, offline-capable and push-enabled. See service workers and manifests.
- [Python](https://nodea.io/en/glossary/python.md): Python is a high-level programming language prized for readability and versatility. Learn its uses in web, data science, AI and automation, and ecosystem.
- [QUIC](https://nodea.io/en/glossary/quic.md): QUIC is a modern UDP-based transport protocol and the foundation of HTTP/3. Learn about faster handshakes, stream multiplexing and built-in TLS encryption.
- [Quota](https://nodea.io/en/glossary/disk-quota.md): A quota is a resource limit (disk space, file count) assigned to a server account. Learn the types of quotas, soft vs hard limits and their use in hosting.
- [RankBrain](https://nodea.io/en/glossary/rankbrain.md): RankBrain is a machine-learning component of Google's algorithm that interprets query intent. Learn how it works, its SEO impact and content optimization.
- [Ranking factors](https://nodea.io/en/glossary/ranking-factors.md): Ranking factors are the signals search engines weigh to order results — content quality, backlinks, page experience and more. See which matter most.
- [Ransomware](https://nodea.io/en/glossary/ransomware.md): Ransomware is malware that encrypts data and demands a ransom to unlock it. Learn its attack vectors, impact and effective defense and backup strategies.
- [Rate limiting](https://nodea.io/en/glossary/rate-limiting.md): Rate limiting caps how many requests a client can send per time window, protecting servers and APIs from overload and abuse. Learn the core algorithms.
- [rDNS](https://nodea.io/en/glossary/rdns-reverse-dns.md): rDNS (reverse DNS) is a lookup that maps an IP address back to a hostname. Learn about the PTR record, the in-addr.arpa zone and its importance for email.
- [React](https://nodea.io/en/glossary/react.md): React is a JavaScript library for building user interfaces from components and a virtual DOM. Learn about JSX, hooks and its use in modern web applications.
- [Real-time marketing](https://nodea.io/en/glossary/real-time-marketing.md): Real-time marketing (RTM) is a brand reacting to current events and trends as they happen. Learn how it works, its benefits, risks and practical examples.
- [REDAXO](https://nodea.io/en/glossary/redaxo.md): REDAXO is a flexible PHP and MySQL CMS popular with agencies. Learn its module architecture, the AddOn system and typical use cases for custom websites.
- [Redis](https://nodea.io/en/glossary/redis.md): Redis is a fast in-memory key-value store used for caching, queues, sessions and real-time counters. Learn how it works and when to reach for it.
- [Refactoring](https://nodea.io/en/glossary/refactoring.md): Refactoring restructures existing code without changing what it does. Learn the common techniques, its purpose and why tests make it safe to do.
- [Referral](https://nodea.io/en/glossary/referral.md): Referral traffic reaches your site through a link on another website. Learn the analytics channel, referral marketing programs and how to measure both.
- [Regression testing](https://nodea.io/en/glossary/regression-testing.md): Regression testing checks that new code changes have not broken previously working features. Learn regression types, automation and its place in CI/CD.
- [Relative link](https://nodea.io/en/glossary/relative-link.md): A relative link points to a resource relative to the current page, with no domain. Learn the relative path types and how they differ from absolute links.
- [Remarketing](https://nodea.io/en/glossary/remarketing.md): Remarketing targets ads at people who already visited your site. Learn how audience lists, tracking pixels and typical retargeting campaigns work.
- [Replication](https://nodea.io/en/glossary/replication.md): Replication copies data across servers in near real time. Learn master-slave and master-master topologies plus synchronous and asynchronous modes.
- [Repository](https://nodea.io/en/glossary/repository.md): A repository stores a project's source code together with its full change history. Learn about Git repos, branches, commits and team collaboration.
- [Responsive Design](https://nodea.io/en/glossary/responsive-design.md): Responsive design lets a page adapt its layout to any screen. Learn how media queries, flexible grids and the mobile-first approach make it work.
- [Responsive display ads](https://nodea.io/en/glossary/responsive-display-ads.md): Responsive display ads (RDAs) are a Google Ads format that automatically fits assets to any ad space. Learn how the format works and where to use it.
- [REST](https://nodea.io/en/glossary/rest.md): REST is an architectural style for HTTP, resource-based APIs. Learn GET/POST/PUT/DELETE, statelessness and how it compares with SOAP and GraphQL.
- [Reverse Proxy](https://nodea.io/en/glossary/reverse-proxy.md): A reverse proxy sits in front of your application and receives client traffic. Learn its role in SSL termination, load balancing, caching and security.
- [Rich Results](https://nodea.io/en/glossary/rich-results.md): Rich results are enhanced Google listings with stars, prices or FAQs. Learn how structured data produces them and how to earn them for your pages.
- [RLSA](https://nodea.io/en/glossary/rlsa.md): RLSA means Remarketing Lists for Search Ads in Google Ads. Learn how to tailor bids and messaging to users who already visited your website.
- [ROAS](https://nodea.io/en/glossary/roas.md): ROAS is Return on Ad Spend: revenue divided by campaign cost. Learn how to calculate ROAS, how to read the result and how it differs from ROI.
- [robots.txt](https://nodea.io/en/glossary/robots-txt.md): robots.txt controls crawler access to a site. Learn the Disallow, Allow and Sitemap directives and the difference between blocking and noindex.
- [rsync](https://nodea.io/en/glossary/rsync.md): rsync is a tool for fast file synchronisation between directories and servers. Learn its delta-transfer algorithm, SSH mode and common uses.
- [RTO and RPO](https://nodea.io/en/glossary/rto-and-rpo.md): RTO and RPO are core disaster recovery metrics. Learn the difference between recovery time and recovery point objectives and how to set them for services.
- [Ruby on Rails](https://nodea.io/en/glossary/ruby-on-rails.md): Ruby on Rails is a web framework written in Ruby built on MVC and convention over configuration. Learn how it works, its strengths and typical use cases.
- [SaaS](https://nodea.io/en/glossary/saas.md): SaaS delivers software as a cloud service, accessed through a browser on a subscription. Learn how it works and how it differs from IaaS and PaaS.
- [Sales funnel](https://nodea.io/en/glossary/sales-funnel.md): A sales funnel models the customer's journey from first contact to purchase. Learn the funnel stages, metrics and how it guides marketing planning.
- [Schema.org](https://nodea.io/en/glossary/schema-org.md): Schema.org is a structured data vocabulary describing content for search engines. Learn schema types, markup formats and how it powers rich results.
- [Screaming Frog](https://nodea.io/en/glossary/screaming-frog.md): Screaming Frog is a crawler for technical SEO audits that scans a site like Googlebot. Learn its features, use cases and the common errors it uncovers.
- [Scrum](https://nodea.io/en/glossary/scrum.md): Scrum is an agile framework for managing work through sprints, roles and events. Learn how it works, the team roles and its practical applications.
- [SCSS](https://nodea.io/en/glossary/scss.md): SCSS is the modern Sass preprocessor syntax that extends CSS with variables, nesting and mixins. Learn how it differs from CSS and how compilation works.
- [SDLC](https://nodea.io/en/glossary/sdlc.md): SDLC is the software development life cycle spanning analysis to maintenance. Learn its phases, popular models and how it applies to real IT projects.
- [Search Intent](https://nodea.io/en/glossary/search-intent.md): Search intent is the goal a user has when typing a query. Learn the types of search intent and why matching content to intent matters for SEO.
- [Security Headers](https://nodea.io/en/glossary/security-headers.md): HTTP security headers protect sites from XSS, clickjacking and downgrade attacks. Learn what CSP, HSTS and X-Frame-Options do and how to deploy them.
- [Segmentation](https://nodea.io/en/glossary/segmentation.md): Segmentation splits an audience into homogeneous groups by shared traits. Learn the criteria, types and uses of segmentation in marketing and email.
- [SEM](https://nodea.io/en/glossary/sem.md): SEM is search engine marketing combining paid ads and SEO. Learn how SEM differs from SEO, the components of a strategy and how it works in practice.
- [SEO](https://nodea.io/en/glossary/seo.md): SEO is optimizing a site for free search results. Learn the on-page, off-page and technical areas of SEO and how visibility is built in Google over time.
- [SEO backlink network](https://nodea.io/en/glossary/seo-backlink-network.md): An SEO backlink network is a set of sites created to link to a target site and boost its rankings. See how it works and the risk it carries.
- [SERM](https://nodea.io/en/glossary/serm.md): SERM is search engine reputation management. Learn how to suppress negative content, build a positive brand image and monitor what search results show.
- [SERP](https://nodea.io/en/glossary/serp.md): A SERP is the search engine results page shown after a query. Learn its elements — organic results, paid ads, snippets and knowledge graphs.
- [Server](https://nodea.io/en/glossary/server.md): A server is a computer or program that provides services and data to devices on a network. Learn the client-server model, server types and their uses.
- [Server logs](https://nodea.io/en/glossary/server-logs.md): Server logs are event records from the web server and system. Learn the types of logs, their structure and their use in diagnostics and SEO analysis.
- [Serverless computing](https://nodea.io/en/glossary/serverless-computing.md): Serverless computing is a cloud model where the provider manages servers and you pay only for actual code execution. Learn how it works and where it fits.
- [SFTP](https://nodea.io/en/glossary/sftp.md): SFTP is a secure file transfer protocol built on SSH. Learn how it works and how it differs from plain FTP and TLS-based FTPS in practical use.
- [SGE](https://nodea.io/en/glossary/sge.md): SGE is Google's generative search experience where AI produces summarised answers. Learn how it affects SEO, click-through rates and organic traffic.
- [Shoper](https://nodea.io/en/glossary/shoper.md): Shoper is a Polish SaaS e-commerce platform for running online stores without maintaining your own server. Learn how it works and how it compares.
- [Short tail](https://nodea.io/en/glossary/short-tail-keywords.md): Short tail keywords are short, broad search terms with high volume and strong competition. Learn how they differ from long tail and their SEO role.
- [Silex](https://nodea.io/en/glossary/silex.md): Silex is a lightweight PHP microframework built on Symfony components, now discontinued. Learn how it worked and why Symfony is its recommended successor.
- [SilverStripe](https://nodea.io/en/glossary/silverstripe.md): SilverStripe is an open-source PHP CMS valued for flexible content modelling and an intuitive editor panel. Learn how it works and where it is used.
- [Simple Machines Forum (SMF)](https://nodea.io/en/glossary/simple-machines-forum-smf.md): SMF (Simple Machines Forum) is a free, open-source PHP forum script for building community discussion boards. Learn how it works and its hosting needs.
- [Single opt-in](https://nodea.io/en/glossary/single-opt-in.md): Single opt-in adds a subscriber to a list without confirming their email. Learn how it differs from double opt-in, its pros, cons and deliverability impact.
- [Sitebulb](https://nodea.io/en/glossary/sitebulb.md): Sitebulb is a crawling and technical SEO audit tool that visualises issues and suggests priorities. Learn its features and practical use in audits.
- [SMO](https://nodea.io/en/glossary/smo.md): SMO (Social Media Optimization) tunes content and your site for social media to boost reach and engagement. Learn the methods and how it relates to SEO.
- [SMTP](https://nodea.io/en/glossary/smtp.md): SMTP is the protocol responsible for sending and relaying email between servers. Learn how it works, which ports to use and its role in deliverability.
- [Snapshot](https://nodea.io/en/glossary/snapshot.md): A snapshot captures the state of a disk or system at a point in time. Learn how snapshots differ from backups and how they are used on VPS servers.
- [Sngine](https://nodea.io/en/glossary/sngine.md): Sngine is a PHP script for building your own social network. Learn its features, hosting requirements and typical use cases for the platform.
- [SNI](https://nodea.io/en/glossary/sni.md): SNI (Server Name Indication) lets one IP address serve many SSL certificates. Learn how this TLS extension works and why it matters for hosting.
- [SOAP](https://nodea.io/en/glossary/soap.md): SOAP is an XML-based protocol for communication between applications. Learn how it works, the message structure and how it differs from REST.
- [Soft bounce](https://nodea.io/en/glossary/soft-bounce.md): A soft bounce is a temporary rejection of an email by the recipient's server. Learn the causes and how it differs from a hard bounce.
- [SPA (Single Page Application)](https://nodea.io/en/glossary/single-page-application.md): A SPA (Single Page Application) is a web app that runs on a single page without reloads. Learn how it works, its benefits and its impact on SEO.
- [Spear phishing](https://nodea.io/en/glossary/spear-phishing.md): Spear phishing is a targeted phishing attack aimed at a specific person or company. Learn how it works, real examples and how to defend against it.
- [SPF](https://nodea.io/en/glossary/spf.md): SPF (Sender Policy Framework) is a DNS record that defines which servers may send mail from your domain. Learn its syntax and role against spoofing.
- [Split-horizon DNS](https://nodea.io/en/glossary/split-horizon-dns.md): Split-horizon DNS returns different answers for the same name depending on who is asking. Learn how it works and its typical use cases.
- [Sponsored article](https://nodea.io/en/glossary/sponsored-article.md): A sponsored article is a paid publication blending editorial content with brand promotion. See how it supports SEO, how to label links and vet publishers.
- [Spring Boot](https://nodea.io/en/glossary/spring-boot.md): Spring Boot is a framework that simplifies building Java apps and microservices. Learn about auto-configuration, the embedded server and common uses.
- [SQL](https://nodea.io/en/glossary/sql.md): SQL is the standard query language for relational databases. Learn the core commands, command groups and how it is used in web applications.
- [SQL injection](https://nodea.io/en/glossary/sql-injection.md): SQL injection is an attack that injects malicious SQL code through input fields. Learn how it works, its consequences and how to defend against it.
- [SRE (Site Reliability Engineering)](https://nodea.io/en/glossary/sre.md): SRE (Site Reliability Engineering) keeps systems reliable through automation. Learn about SLOs, error budgets and how SRE differs from DevOps.
- [SRV record](https://nodea.io/en/glossary/srv-record.md): An SRV record names the host and port of a specific network service for a domain. Learn its structure, the priority, weight and port fields and its uses.
- [SSD (Solid State Drive)](https://nodea.io/en/glossary/ssd-drive.md): An SSD stores data in NAND flash with no moving parts, cutting access times from milliseconds to microseconds. See how SSDs work and why servers rely on them.
- [SSH](https://nodea.io/en/glossary/ssh.md): SSH (Secure Shell) is a protocol for encrypted remote access to a server. Learn how it works, key-based authentication and common use cases.
- [SSH key](https://nodea.io/en/glossary/ssh-key.md): An SSH key is a cryptographic key pair for passwordless, secure server login. Learn about the private and public key and how to use them safely.
- [SSL](https://nodea.io/en/glossary/ssl.md): SSL encrypts the connection between a browser and a server, today handled by TLS. Learn the role of the certificate, HTTPS and certificate types.
- [Structured data](https://nodea.io/en/glossary/structured-data.md): Structured data is machine-readable markup, usually schema.org in JSON-LD, that describes page content to search engines and unlocks rich results.
- [Subdomain](https://nodea.io/en/glossary/subdomain.md): A subdomain is the part of an address that precedes the main domain, e.g. shop.yourcompany.com. Learn its structure, DNS setup and practical uses.
- [Supplemental index](https://nodea.io/en/glossary/supplemental-index.md): The supplemental index was Google's former secondary index for low-quality pages. Learn its history, SEO meaning and its modern equivalents in indexing.
- [Svelte](https://nodea.io/en/glossary/svelte.md): Svelte is a JavaScript framework that compiles components to plain code with no virtual DOM. Learn how it works, its advantages and uses in building interfaces.
- [SVG](https://nodea.io/en/glossary/svg.md): SVG is an XML-based vector graphics format that scales without quality loss. Learn its structure, how it differs from raster images and its uses on the web.
- [Swipe up](https://nodea.io/en/glossary/swipe-up.md): Swipe up is an upward finger gesture, popular in Stories for opening a link. Learn how it works, the history of the Instagram feature and its marketing uses.
- [SWOT analysis](https://nodea.io/en/glossary/swot-analysis.md): SWOT analysis maps strengths, weaknesses, opportunities and threats. Learn the matrix, how to build it and its use in strategy and online marketing.
- [Symfony](https://nodea.io/en/glossary/symfony.md): Symfony is a modular PHP framework built from reusable components. Learn its architecture, ecosystem and uses in large, scalable web applications.
- [Target attribute](https://nodea.io/en/glossary/target-attribute.md): The target attribute controls where a link opens — same or new tab. Learn the \_blank and \_self values, the tabnabbing risk and why rel noopener matters.
- [TDD](https://nodea.io/en/glossary/tdd.md): TDD is a development practice where you write a failing test before the code that makes it pass. See how the red-green-refactor cycle shapes better code.
- [Template](https://nodea.io/en/glossary/template.md): A template is a ready-made layout with fixed structure and placeholders for content. See how templates speed up building websites, emails and documents.
- [TikiWiki](https://nodea.io/en/glossary/tikiwiki.md): TikiWiki is an open-source PHP CMS and wiki combining wiki, blog, forum and gallery in one platform. Learn its features, requirements and use cases.
- [Tiny text](https://nodea.io/en/glossary/tiny-text.md): Tiny text is a black hat SEO trick that hides text behind a tiny font size. Learn why Google penalises tiny text and how this hidden-text manipulation works.
- [Title tag](https://nodea.io/en/glossary/title-tag.md): The title tag is the page title shown in search results and the browser tab. Learn its SEO impact, optimal length and rules for writing effective titles.
- [TLD](https://nodea.io/en/glossary/tld.md): A TLD is a top-level domain — the ending of an address such as .com, .org or .pl. Learn TLD types (gTLD, ccTLD, new TLDs) and their role in the DNS.
- [TLS](https://nodea.io/en/glossary/tls.md): TLS is the protocol that encrypts internet connections and the successor to SSL. Learn the handshake, TLS 1.2 and 1.3, and the role of certificates and HTTPS.
- [TLS-RPT](https://nodea.io/en/glossary/tls-rpt.md): TLS-RPT is a standard for reporting TLS encryption problems in email delivery. Learn the \_smtp.\_tls TXT record, how it pairs with MTA-STS and report format.
- [Topical authority](https://nodea.io/en/glossary/topical-authority.md): Topical authority is a site's recognised expertise on a subject, built by covering it thoroughly. See how depth of content strengthens SEO rankings.
- [TOTP](https://nodea.io/en/glossary/totp.md): TOTP is a time-based one-time password used in two-factor authentication apps. See how the rotating 6-digit codes are generated and why they add security.
- [tracert](https://nodea.io/en/glossary/tracert.md): tracert traces the network path packets take to a destination, listing each router hop and its latency. See how it helps diagnose slow or failing routes.
- [Trailing slash](https://nodea.io/en/glossary/trailing-slash.md): A trailing slash is the / at the end of a URL. See why the version with and without it can be treated as two different pages and how to avoid SEO issues.
- [Transient](https://nodea.io/en/glossary/transient.md): A transient is a piece of temporary, cached data stored with an expiry time. See how transients speed up sites by avoiding repeated expensive operations.
- [Transpiler](https://nodea.io/en/glossary/transpiler.md): A transpiler converts source code from one language or version into another at the same level, such as modern JavaScript into an older, compatible form. See how it works.
- [TrueView Discovery ads](https://nodea.io/en/glossary/trueview-discovery-ads.md): TrueView Discovery ads show a video thumbnail with text in YouTube results and suggestions. Learn how they work, how they are billed and where they fit.
- [TrueView In-Stream ads](https://nodea.io/en/glossary/trueview-in-stream-ads.md): TrueView In-Stream are skippable video ads billed per view (CPV). Learn how they work, the threshold that triggers a charge and where to use them.
- [Trust Flow](https://nodea.io/en/glossary/trust-flow.md): Trust Flow is a metric that scores a site's link quality by how close its backlinks are to trusted sources. See how it differs from raw link quantity.
- [TTFB](https://nodea.io/en/glossary/ttfb.md): TTFB measures how long it takes for the first byte of a response to reach the browser after a request. See what a high TTFB reveals about server speed.
- [TTL](https://nodea.io/en/glossary/ttl.md): TTL defines how long data such as a DNS record or cached response stays valid before it must be refreshed. See how it controls propagation and caching.
- [Two-Factor Authentication (2FA)](https://nodea.io/en/glossary/two-factor-authentication.md): Two-factor authentication (2FA) adds a second verification step to login, such as a TOTP code. Learn the methods, how it works and its security benefits.
- [TXT Record](https://nodea.io/en/glossary/txt-record.md): A TXT record stores arbitrary text in a DNS zone. Learn how it powers SPF, DKIM and DMARC email authentication and domain ownership verification.
- [TypeScript](https://nodea.io/en/glossary/typescript.md): TypeScript is a typed superset of JavaScript that adds static types and compiles to plain JavaScript. See how types catch errors before code runs.
- [TYPO3](https://nodea.io/en/glossary/typo3.md): TYPO3 is an open-source enterprise CMS written in PHP, aimed at large, multilingual sites. See how it differs from lighter systems like WordPress.
- [UGC](https://nodea.io/en/glossary/ugc.md): UGC is content created by users rather than a brand — reviews, comments, photos and posts. See how it builds trust and what it means for SEO.
- [UI](https://nodea.io/en/glossary/ui.md): UI is the visual layer users interact with — layout, colours, buttons and typography. See how it relates to UX and why both matter for a product.
- [Unit testing](https://nodea.io/en/glossary/unit-testing.md): Unit testing verifies individual pieces of code in isolation. Learn the AAA pattern, mocking, code coverage and where unit tests fit in a CI/CD pipeline.
- [Up-selling](https://nodea.io/en/glossary/up-selling.md): Up-selling encourages a customer to buy a higher-end or upgraded version of a product. See how it differs from cross-selling and boosts order value.
- [Uptime monitoring](https://nodea.io/en/glossary/uptime-monitoring.md): Uptime monitoring continuously checks whether a site or service is available and alerts you when it goes down. See how checks and alerts work.
- [URL](https://nodea.io/en/glossary/url.md): A URL is the web address that identifies and locates a resource online. See how its parts — scheme, domain and path — direct a browser to a page.
- [URL Rating](https://nodea.io/en/glossary/url-rating.md): URL Rating scores the link strength of a single page on a scale, based on its backlink profile. See how it differs from domain-level metrics.
- [User Agent](https://nodea.io/en/glossary/user-agent.md): A user agent is software acting on a user's behalf, such as a browser, and the string it sends identifying itself. See how servers use it.
- [User Journey](https://nodea.io/en/glossary/user-journey.md): A user journey is the full path a person takes to accomplish a goal with a product, across every step and touchpoint. See why mapping it improves UX.
- [UX](https://nodea.io/en/glossary/ux.md): UX is the whole experience a person has when using a digital product. See what shapes user experience and why it directly affects conversion.
- [Varnish Cache](https://nodea.io/en/glossary/varnish-cache.md): Varnish Cache is a high-performance HTTP accelerator that caches responses and offloads the application server. See how it speeds up high-traffic sites.
- [vBulletin](https://nodea.io/en/glossary/vbulletin.md): vBulletin is commercial software for running discussion forums, written in PHP. See how it works and what sets it apart from other platforms.
- [Vector graphics](https://nodea.io/en/glossary/vector-graphics.md): Vector graphics describe images with geometric shapes, so they scale to any size without quality loss. Learn the difference from raster, formats and uses.
- [Version control](https://nodea.io/en/glossary/version-control.md): Version control is a system that tracks every change to a project's files. Learn how VCS works, the role of Git and its use in team collaboration.
- [Versioning](https://nodea.io/en/glossary/versioning.md): Versioning is the systematic labelling of successive versions of code, files or an API. See how a version control system works and why releases are numbered.
- [Viewport](https://nodea.io/en/glossary/viewport.md): The viewport is the visible area of a page in the browser window, key to responsiveness. See how the meta viewport affects display on phones.
- [Virtual DOM](https://nodea.io/en/glossary/virtual-dom.md): The Virtual DOM is a lightweight in-memory copy of the page structure that frameworks compare with the real one to update only what changed. See how it works.
- [Virtualization](https://nodea.io/en/glossary/virtualization.md): Virtualization lets many isolated systems run on one physical machine. See how it works and how it makes VPS services and the cloud possible.
- [Volumetric attack](https://nodea.io/en/glossary/volumetric-attack.md): A volumetric attack is a DDoS variant that saturates the victim's bandwidth. Learn about amplification, reflection and how to defend against link flooding.
- [VPN](https://nodea.io/en/glossary/vpn.md): A VPN is an encrypted tunnel that connects a device to a network over the internet. See how a virtual private network works and what it is used for.
- [VPS](https://nodea.io/en/glossary/vps.md): A VPS is a virtual private server with guaranteed resources running on a shared physical machine. See how it differs from shared hosting.
- [Vue.js](https://nodea.io/en/glossary/vue-js.md): Vue.js is a progressive JavaScript framework for building user interfaces. See how its reactive model works and how it compares to React and Angular.
- [WCAG](https://nodea.io/en/glossary/wcag.md): WCAG is the international set of web content accessibility guidelines. See the principles they rest on and the levels of conformance they define.
- [WCAG 2.2](https://nodea.io/en/glossary/wcag-2-2.md): WCAG 2.2 is the latest version of the accessibility guidelines, adding criteria on touch targets and help. See what has changed.
- [WebAssembly](https://nodea.io/en/glossary/webassembly.md): WebAssembly (Wasm) is a low-level binary format that runs in the browser at near-native speed. See how it works with JavaScript.
- [Webflow](https://nodea.io/en/glossary/webflow.md): Webflow is a visual site builder that combines no-code design with clean generated HTML and CSS. See who it is a good choice for.
- [Webhook](https://nodea.io/en/glossary/webhook.md): A webhook is an automatic HTTP notification one service sends to another when an event occurs. See how it differs from a traditional API.
- [Webinar](https://nodea.io/en/glossary/webinar.md): A webinar is an interactive seminar run over the internet in real time. See how it works, what it is used for and how it differs from a recording.
- [Webmail](https://nodea.io/en/glossary/webmail.md): Webmail is access to email through a browser, without installing a mail program. See how it works and how it differs from an IMAP/POP3 client.
- [WebP](https://nodea.io/en/glossary/webp.md): WebP is a modern image format from Google offering better compression than JPEG and PNG. See how it affects loading speed and Core Web Vitals.
- [Webpack](https://nodea.io/en/glossary/webpack.md): Webpack is a bundler that combines JavaScript, CSS and assets into optimised packages. See how it works and why the modern front-end needs it.
- [Website](https://nodea.io/en/glossary/website.md): A website is a document available on the web under a URL. Learn how it is built, the difference between a page and a site, and what it takes to make it work online.
- [White Hat SEO](https://nodea.io/en/glossary/white-hat-seo.md): White Hat SEO is optimisation that follows search engine guidelines, based on quality and value for the user. See how it differs from black hat techniques.
- [WHMCS](https://nodea.io/en/glossary/whmcs.md): WHMCS is a platform for automating sales and client management at hosting companies. See how it combines billing, provisioning and support in one system.
- [WHOIS](https://nodea.io/en/glossary/whois.md): WHOIS is a protocol and public database with domain registration details. See what data it holds and how privacy protection affects it.
- [Widget](https://nodea.io/en/glossary/widget.md): A widget is a self-contained, reusable interface element or content block embedded on a page. See the most common types of widgets.
- [Wildcard DNS](https://nodea.io/en/glossary/wildcard-dns.md): Wildcard DNS is a record covering all undefined subdomains in a domain. See how the asterisk works in DNS and what it is used for.
- [Wireframe](https://nodea.io/en/glossary/wireframe.md): A wireframe is a simplified sketch of a page layout showing the placement of elements without graphics. See how it differs from a mockup and a prototype.
- [WooCommerce](https://nodea.io/en/glossary/woocommerce.md): WooCommerce is a plugin that turns WordPress into an online store. See how it works, what it offers and who it is a good choice for.
- [WordPress](https://nodea.io/en/glossary/wordpress.md): WordPress is the world's most popular CMS, powering over 40% of websites. See how it works, what it consists of and why it dominates the market.
- [WYSIWYG](https://nodea.io/en/glossary/wysiwyg.md): WYSIWYG is an editor where content looks the same while editing as when published. See how it works and its advantages and limitations.
- [XML Sitemap](https://nodea.io/en/glossary/xml-sitemap.md): An XML sitemap is a file listing a site's URLs to help search engines discover and index pages. Learn its structure and best practices for SEO.
- [XOOPS](https://nodea.io/en/glossary/xoops.md): XOOPS is an open-source, modular CMS written in PHP, aimed at building community portals. See how its module architecture works.
- [XSS](https://nodea.io/en/glossary/xss.md): XSS is an attack that injects a malicious script into a page shown to other users. See how it works and how to defend against it.
- [Yarn](https://nodea.io/en/glossary/yarn.md): Yarn is a package manager for JavaScript, an alternative to npm, focused on speed and reproducible installs. See how it works and what sets it apart.
- [Yii Framework](https://nodea.io/en/glossary/yii-framework.md): Yii is a high-performance PHP framework for building web applications, based on the MVC pattern. See how it stands out against Laravel and Symfony.
- [YMYL](https://nodea.io/en/glossary/ymyl.md): YMYL is a category of content that can affect a reader's health, safety or finances. See why Google evaluates it especially strictly.
- [Zend Framework](https://nodea.io/en/glossary/zend-framework.md): Zend Framework is an enterprise-grade modular PHP framework, continued today as Laminas. See how its component architecture worked.
- [Zenphoto](https://nodea.io/en/glossary/zenphoto.md): Zenphoto is an open-source CMS specialised in publishing photo and media galleries. See how it works and who it is a good choice for.
- [Zero Trust](https://nodea.io/en/glossary/zero-trust.md): Zero Trust is a security model based on the principle "never trust, always verify". See how it changes the approach to network and access protection.
- [Zero-click searches](https://nodea.io/en/glossary/zero-click-searches.md): Zero-click searches are queries where the user gets the answer on the results page without visiting any site. See how they affect traffic.

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Site index: [llms.txt](https://nodea.io/en/llms.txt)