The Alto and Ethernet System
Xerox PARC in the 1970’s

Butler Lampson

October 17, 2006


A substantial computing system based on the Alto was developed at the Xerox Palo Alto Research Center between 1973 and 1978, and was considerably extended between 1978 and 1983. The hardware base for this system is simple and uniform, if somewhat unconventional. The software, which gives the system its visible form and knits together its many parts, is by contrast complex, variegated, even ramified. It is convenient to call the whole complex of hardware and software "the Alto system". This talk describes the major components of the Alto system. It also tries to explain why the system came out as it did, by tracing the ideas that influenced it, the way these ideas evolved into the concept of personal distributed computing, and the nature of the organization that built the Alto. Finally, it sketches the systems and companies derived from the Alto and discusses how Xerox was both successful and spectacularly unsuccessful in exploiting the work done at PARC .




PowerPoint, Acrobat, HTML. Here are papers on the Alto hardware and software, and an earlier one on the Alto system.


A video of the talk I gave in Ed Lazowska’s course (CSEP 590A, History of Computing) at the University of Washington and UC Berkeley in Autumn 2006 is here.