Graphical user interface
GUI, pronounced like "gooey", stands for Graphical User Interface, a human-computer interaction method that uses graphical images in addition to text.
It typically uses widgets such as menus, buttons, radio boxes, and icons,
and usually employs a pointing device (such as mouse, trackball, or touchscreen)
in addition to a keyboard.
Examples of GUIs include Mac OS, Microsoft Windows, and the
X Window System (including KDE and GNOME).
Similar to GUIs are TUIs, or text user interfaces, that display the same types of widgets in a character-cell mode rather than in a pixel mode;
examples include the interfaces of many ncurses and MS-DOS applications.
Contrast with CLI, which takes input on a command line.
Because GUIs and TUIs tend to show most or all relevant categories of commands on the display, users often learn them faster than CLIs,
but users with vision or motion disability often have trouble navigating in a GUI,
and most commercial GUIs use at least an order of magnitude more computer power than a CLI, making a GUI unwieldy on older hardware.
See also History of the GUI, human-computer interaction
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