What is a command-line interface (CLI)? 

A Command-Line Interface (CLI) is a text-based interface used in operating systems or software applications where users interact with the system by typing commands. In a CLI, users enter commands at a prompt, which are then interpreted and executed by the operating system or application. CLI environments typically provide a wide range of commands for performing tasks such as file management, system configuration, network operations, and software development. Examples include the command prompt in Windows, Terminal on macOS and Linux, and shells like Bash and PowerShell.