AutoCAD is a 2D and 3D computer-aided design (CAD) software application developed by Autodesk. AutoCAD was derived from a program that began in 1977, and then released in 1979 called Interact CAD, also referred to in early Autodesk documents as MicroCAD, which was written prior to Autodesk's (then Marinchip Software Partners) formation by Autodesk cofounder Michael Riddle. The first version by Autodesk was demonstrated at the 1982 Comdex and released that December. AutoCAD supported CP/M-80 computers. As Autodesk's flagship product, by March 1986 AutoCAD had become the most ubiquitous CAD program worldwide. The first UNIX version was Release 10 for Xenix in October 1989, while the first version for Windows was Release 12, released in February 1993.