---
title: "CLI"
description: "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."
url: "https://nodea.io/en/glossary/cli"
lang: "en"
updated: "2026-07-13"
---

# CLI

> CLI is a command line interface that lets you control a system or application by typing text commands instead of clicking within a graphical interface.

**CLI** (Command Line Interface) is a way of communicating with a computer in which the user issues commands by typing them as text, and the system responds with text messages. Instead of clicking icons and windows as in a graphical interface, the operator types commands — for example to browse files, run programs or configure services. The CLI is a core tool for system administrators and developers.

## How the CLI works

The command line is handled by a program called a **shell**, such as Bash, Zsh or PowerShell. The shell reads the typed command, interprets it, launches the appropriate program and returns the result. Commands can be chained into pipelines, their output redirected to files, and saved in scripts — which makes it possible to automate repetitive tasks.

Remote work on a server usually happens over the [SSH](https://nodea.io/en/glossary/ssh) protocol, which creates an encrypted connection to the terminal of a remote machine. On Windows, the [PuTTY](https://nodea.io/en/glossary/putty) tool is popular for such connections. Many applications also ship their own CLI — for example development tools or package managers.

## Practical applications

The command line interface is indispensable wherever speed, precision and automation matter.

- **Server administration** — installing packages, configuring services and reviewing [server logs](https://nodea.io/en/glossary/server-logs) happen mainly through the CLI.
- **Automation** — scripts triggered by [cron](https://nodea.io/en/glossary/cron) run CLI commands with no human involvement.
- **Development work** — version control, building projects and deployments are frequently done from the terminal.

On VPS servers without a graphical interface, the CLI is the primary — and often the only — way to manage the machine. Mastering the command line significantly speeds up daily work with infrastructure.

### How does CLI differ from a GUI?

A CLI is a text interface where you issue commands by typing, while a GUI is a graphical interface operated with a mouse and windows. The CLI is faster and easier to automate but requires knowing the commands.

### Do I need SSH to work in the CLI?

For local CLI work a terminal on your own computer is enough. To control a remote server via the command line you typically connect over the SSH protocol, which encrypts the entire session.

## Related

- [SSH](https://nodea.io/en/glossary/ssh)
- [PuTTY](https://nodea.io/en/glossary/putty)
- [Cron](https://nodea.io/en/glossary/cron)
- [Server](https://nodea.io/en/glossary/server)
- [Interface](https://nodea.io/en/glossary/interface)

---

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