As Autodesk's flagship product, by March 1986 AutoCAD had become the most ubiquitous CAD program worldwide. The first version by Autodesk was demonstrated at the 1982 Comdex and released that December. Introduction 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.