A command line interface (CLI) is a text-based way to interact with a computer's operating system. Users type commands into a console or terminal to perform tasks, such as managing files or running programs. Unlike graphical user interfaces (GUIs), which use visual elements like buttons and icons, CLIs rely solely on text input and output. CLIs are often preferred by advanced users and developers because they can be more efficient for executing repetitive tasks. Popular examples of command line interfaces include the Windows Command Prompt, Linux Bash, and macOS Terminal. These tools allow for powerful scripting and automation capabilities.