A command line interface (CLI) is a method of interacting with an operating system or software using a command line interpreter. This command line interpreter may be a text terminal, terminal emulator, or remote shell client such as PuTTY.
The concept of the CLI originated when teletype machines (TTY) were connected to computers in the 1950s, and offered results on demand, compared to 'batch' oriented mechanical punch card input technology. Dedicated text-based CRT terminals followed, with faster interaction and more information visible at one time, then graphical terminals enriched the visual display of information. Currently personal computers encapsulate both functions in software.
The CLI continues to coevolve with graphical user interfaces (GUIs) like those provided by Microsoft Windows, Mac OS and the X Window System. In some applications, such as MATLAB, a CLI is integrated with the GUI, with the benefits of both.
