Aninterface orshell is what the user uses[1] on anoperating system to make the computer do tasks, like writing a document, or loading aweb page. There are two types of interfaces, acommand line interface (CLI for short) - where people write commands to make the computer perform tasks, or agraphical user interface (GUI for short), where people use theirComputer mouse to click on buttons to perform tasks.
Command line interfaces ask the user to type in commands in atext-based environment, not allowing images, like the screen image to the right.[2]
For example, if the user wanted the computer to say "Hello World", he or she would:
This is hard to use for most people, mostly because when the user has to do a long command, he or she can miss a letter or two, so the computer shows an error, and he or she has to do it all over again, which can waste hours.
Graphical user interfaces are instead made of not only text, but also images. The first computer to do this was theApple Lisa (1983).
The followingoperating systems can use graphical user interfaces:
Since the top operating systems (listed above) use graphical user interfaces, they are seen on every computer. Anyone can still use a command line interface on any computer very easily.
