Command Line Interface is also known as CLI. This is an interface for users to interact and instruct system in command line fashion. CLI is the basis on text-based interact to accept user request and response. While comparing with GUI, CLI is lightweight and consume less CPU & Memory resources. considering the GUI of different versions and flavour, User needs to change there way of working and need additional learning. Whereas CLI is independent of this and allows the user to use any Linux system in the same manner. CLI also comes up with help option so that users need not remember all commands and option and they can refer help or man page for details options and definitions. Advantages Easy, Fast & Flexible Very less load on CPU or Memory Disadvantages Commands syntax is a bit tricky and tough to learn Long Text inputs can be problematic In Compare of GUI, bit tuff to use