In computing, the desktop metaphor is an interface metaphor which is a set of unifying concepts used by graphical user interfaces to help users interact more easily with the computer. The desktop metaphor treats the computer monitor as if it is the user's desktop, upon which objects such as documents and folders of documents can be placed. A document can be opened into a window, which represents a paper copy of the document placed on the desktop. Small applications called desk accessories are also available, such as a desk calculator or notepad, etc.
The desktop metaphor itself has been extended and stretched with various implementations of desktop environments, since access to features and usability of the computer are usually more important than maintaining the ‘purity’ of the metaphor. Hence we find trash cans on the desktop, as well as disks and network volumes (which can be thought of as filing cabinets—not something normally found on a desktop). Other features such as menu bars, task bars, or docks have no counterpart on a real-world desktop.
The desktop metaphor was first introduced by Alan Kay at Xerox PARC in 1970 and elaborated in a series of innovative software applications developed by PARC scientists throughout the ensuing decade. The first computer to use an early version of the desktop metaphor was the experimental Xerox Alto, and the first commercial computer that adopted this kind of interface was the Xerox Star. The use of window controls to contain related information predates the desktop metaphor, with a primitive version appearing in Douglas Engelbart's "Mother of All Demos", though it was incorporated by PARC in the environment of the Smalltalk language.