A CLI comes with a command line interpreter that interprets the command and implements it. The command line interpreter might be running in a text terminal or in a terminal emulator windows as a remote shell. Once the command finishes execution, the output of that command might be in the form of a text displayed on the interface itself (MSCOM, 2007).
The concept of CLI emerged when teletypewriter machines used to connected to computers in 1950s, and gave results on the demand as compared to other technologies such as batch based punched card inputs used during those times. After the success of the initial CLIs, next came the CRT based terminals that had the capability of interacting faster, they could display more information, and the development kept on going. Currently, the personal computers of today have all three forms of processing, i.e. batch processing, GUI and CLI.
CLIs are complex, and most non-computer people prefer not to use it. This is why, it is often assumed that CLIs have become extinct and they are no longer used. However, it is not the case as CLIs continue to grow alongside the GUIs provided by Microsoft Windows, Mac OS, Linux, etc. Several application also utilize the CLI and mix it with GUI to achieve better results. An example of such application software is MATLAB, and AutoCAD. Besides being embedded with different applications, all the operating systems implemented on the routers, switches, etc. for networking have CLI based operating systems.
The application of CLI is when we have a large number of commands or queries available along with different options and we can give those commands faster than we can using a GUI. The command shells of various operating systems that come with Windows, Linux, Mac Os, etc. work on similar base. Some programming languages such as BASIC, Python, Forth, LISP, etc all provide a modified interactive version of command line interface. Another major application of CLI is its use in engineering and