A CLI or command line interface is a form of interaction when the user types commands and the system responds. It has some similarities to chat-style interfaces, but while the chat allows free text, the CLI has a fixed set of commands, often with obscure names and a fixed syntax for command parameters or options.
At one stage CLI would have bee regarded as old fashioned, superceded by the GUI, or the domain of hackers, but the CLI has experienced a resurgence due to those wanting more precise control over agentic AI.
Used in glossary entries: GUI
Entering a command at a UNIX terminal