Xerox PARC, 1977. System and application programming for proprietary hardware: Alto, Dolphin, Dorado and Dandelion. Pascal-like syntax, ALGOL68-like semantics. An early version was weakly typed. Mesa's modules with separately compilable definition and implementation parts directly led to Wirth's design for Modula. Threads, coroutines (fork/join), exceptions, and monitors. Type checking may be disabled. Mesa was used internally by Xerox to develop ViewPoint, the Xerox Star, MDE, and the controller of a high-end copier. It was released to a few universitites in 1985. Succeeded by Cedar.["Mesa Language Manual", J.G. Mitchell et al, Xerox PARC, CSL-79-3 (Apr 1979)]. ["Early Experience with Mesa", Geschke et al, CACM 20(8):540-552 (Aug 1977)].