Interface metaphor

In user interface design, an interface metaphor is a set of user interface visuals, actions and procedures that exploit specific knowledge that users already have of other domains. The purpose of the interface metaphor is to give the user instantaneous knowledge about how to interact with the user interface. They are designed to be similar to physical entities but also have their own properties (e.g., desktop metaphor and web portals). They can be based on an activity, an object (skeuomorph), or a combination of both and work with users' familiar knowledge to help them understand 'the unfamiliar', and placed in the terms so the user may better understand. An example of an interface metaphor is the and folder analogy for the of an operating system. Another example is the tree view representation of a file system, as in a . In the mid-twentieth century, computers were extremely rare and used only by specialists. They were equipped with complicated interfaces comprehensible only to these select few. In 1968, Douglas Engelbart gave a demonstration which astonished executives at Xerox. They began work on what would eventually become the Xerox Alto. In 1973, Xerox completed work on the first personal computer, the Xerox Alto, which had a sophisticated graphical user interface (GUI) involving windows, icons, menus and a pointer. (WIMP) Unfortunately, the Xerox Alto, and its successor the Xerox Star were far too expensive for the average consumer, and suffered from poor marketing. In 1984 Apple Computer launched the Apple Macintosh, which was the first affordable and commercially successful personal computer to include a graphical user interface. The Macintosh was the second Apple Computer to ship with a graphical user interface, with the Apple Lisa being the first. In 1985, Microsoft released Microsoft Windows which bore a striking resemblance to both Macintosh, and to the Alto's interface. Windows eventually overtook Apple in the PC market to become the predominant GUI-based operating system.