Computer icon

In computing, an icon is a pictogram displayed on a computer screen in order to help the user navigate a computer system or mobile device. The icon itself is a quickly comprehensible symbol of a software tool, function, or a data file, accessible on the system and is more like a traffic sign than a detailed illustration of the actual entity it represents. It can serve as an electronic hyperlink or file shortcut to access the program or data. The user can activate an icon using a mouse, pointer, finger, or recently voice commands. Their placement on the screen, also in relation to other icons, may provide further information to the user about their usage. In activating an icon, the user can move directly into and out of the identified function without knowing anything further about the location or requirements of the file or code.

Icons as parts of the graphical user interface of the computer system, in conjunction with windows, menus and a pointing device (mouse), belong to the much larger topic of the history of the graphical user interface that has largely supplanted the text-based interface for casual use.

Graphically, the icon is a stylized picture of objects that users are familiar with from office environment or from other professional arenas. One group of icons was taken from the symbols found across all electronic devices, such as the power on/off symbol and the USB icon.

Another group is metaphorically representing desktop objects from the 1980s office environment. A third group of icons are the brand icons used to identify commercial software programs. These commercial icons serve as functional links on the system to the program or data files created by a specific software provider. Although icons are usually depicted in graphical user interfaces, icons are sometimes rendered in a TUI using special characters such as MouseText or PETSCII.

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