The Xerox Alto is the first computer designed from its inception to support an operating system based on a graphical user interface (GUI), later using the desktop metaphor. The first machines were introduced on 1 March 1973, a decade before mass-market GUI machines became available. The Alto is contained in a relatively small cabinet and uses a custom central processing unit (CPU) built from multiple SSI and MSI integrated circuits. Each machine cost tens of thousands of dollars despite its status as a personal computer. Only small numbers were built initially, but by the late 1970s, about 1,000 were in use at various Xerox laboratories, and about another 500 in several universities. Total production was about 2,000 systems. The Alto became well known in Silicon Valley and its GUI was increasingly seen as the future of computing. In 1979, Steve Jobs arranged a visit to Xerox PARC, in which Apple Computer personnel would receive a demonstration of the technology from Xerox in exchange for Xerox being able to purchase stock options in Apple. After two visits to see the Alto, Apple engineers used the concepts to introduce the Apple Lisa and Macintosh systems. Xerox eventually commercialized a heavily modified version of the Alto concepts as the Xerox Star, first introduced in 1981. A complete office system including several workstations, storage and a laser printer cost as much as $100,000, and like the Alto, the Star had little direct impact on the market.