Digital Research
Digital Research, Inc. (a.k.a. DR or DRI; originally Intergalactic Digital Research) was the company created by Dr. Gary Kildall to market and develop his CP/M operating system and related products. It was the first large software company in the microcomputer world. Digital Research was based in Pacific Grove, California.
The company's operating systems, starting with CP/M for 8080/Z80-based microcomputers, were the de facto standard of their era, as MS-DOS and MS Windows came later. DR's product suite included the original CP/M and its various offshoots; DR-DOS which was a MS-DOS compatible version of CP/M, and MP/M, the multi-user CP/M. The first 16-bit system was CP/M-86, which was to be unsuccessful in competition with MS-DOS. There followed Concurrent CP/M, a single-user version of the multi-tasking MP/M-86 featuring "virtual consoles" from which applications could be launched to run concurrently. Successive revisions of this system, which gradually supported MS-DOS applications and the FAT filesystem, were labelled Concurrent DOS, Concurrent DOS XM and Concurrent DOS 386.