Using programs and commands that do not have a graphical user interface (GUI) but are rather controlled by typing text commands into a terminal program, or shell.

A command-line interface () is a mechanism for interacting with a computer operating system or software by typing commands to perform specific tasks. This text-only interface contrasts with the use of a mouse pointer with a graphical user interface () to click on options, or menus on a text user interface (TUI) to select options.

This method of instructing a computer to perform a given task is referred to as entering a command. The system waits for the user to conclude the submitting of the text command by pressing the Enter key (a descendant of the carriage return key of a typewriter keyboard). A command-line interpreter then receives, parses, and executes the requested user command.

Upon completion, the command usually returns output to the user in the form of text lines on the CLI.

Related tag:

See also: Wikipedia Command-line_interface.

NOTE: Questions relating to programming (purely about the language, syntax, or runtime errors) belong at Stack Overflow where programming questions are best asked and answered. Be sure to use this tag when having issues interferring on macOS only.

Code Language (used for syntax highlighting): lang-sh