Graphical User Interface (GUI) is a kind of user interface in which elements (menus, buttons, icons, lists, etc.) presented to the user on the display, are executed in the form of graphic images.
In the GUI, the user has random access (through input devices such as a keyboard, mouse, joystick, etc.) to all visible display objects (interface elements) and directly manipulates them. Most often, GUI interface elements are implemented on the basis of metaphors, and display their purpose and properties, which facilitates the understanding and mastering of programs by untrained users.
The graphical user interface is part of the user interface (UI) and defines interaction with the user at the level of visualized information.
One of the requirements for a good graphical interface of the software application is the concept of "Do What I Mean". DWIM requires that the system works in a predictable way so that the user intuitively knows in advance what action the program will perform after receiving the command.
Examples of systems using the GUI: Mac OS, Android, iOS, Microsoft Windows, GNU / Linux, GEM, Solaris, Atari TOS, BeOS, MeeGo.