The term Graphical User Interface came into existence in 1970s that give the difference between text-based graphical interfaces as command line interface. Nowadays all the digital interfaces are GUIs. Abbreviated as GUIs is a user interface that gives graphical elements such as window, icons and buttons. For several generations GUIs was controlled by mouse and keyboard because both of them are sufficient to fulfil the requirement of desktop computers, But in cell phones you cannot mouse and keyboard for that mobile operating system are designed to use touch screen interface.
A true GUI is the one which make it easier to move data from one application another and follow some standard formats to represent graphics. Because formats are well defined and run under the common GUI that can share data.
Basically GUI use windows, menu, icons to navigate to different windows and menu and for that it use mouse which is input device you can also keyboard and some of them shortcuts to done your task.
One of the main advantage of using GUI intended applications are that, they are user friendly for the non-technical persons also attractive and speed up the user’s work. It looks more professional. This is all about user side but we talk about in terms of developers point of view or designers then it require less training and less experience.