A command-line interface (CLI), sometimes called a command-line shell, is a means of interacting with software via commands – each formatted as a line of text. Command-line interfaces emerged in the mid-1960s, on computer terminals, as an interactive and more user-friendly alternative to the non-interactive mode available with punched cards.
For nearly three decades, a CLI was the most common interface for software, but today a graphical user interface (GUI) is more common. Nonetheless, many programs such as operating system and software development utilities still provide CLI.