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 became later. Digital Research was purchased by Novell in 1991, primarily for Novell to gain access to the OS line. 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.
DR produced a selection of programming language compilers and interpreters for their OS-supported platforms, including C, Pascal, COBOL, Forth, PL/I, BASIC, and Logo. They also produced a microcomputer version of the GKS graphics standard (related to NAPLPS) called '''[[GSX''']], and later used this as the basis of their GEM GUI. Less known are their application programs, limited largely to the GSX-based [[DR Draw]] and a small suite of GUI programs for GEM.
Digital Research made the Multiuser DOS utility, which allowed multiple users to run DOS programs concurrently on the same computer.
In a 1991 interview in ''Computer Reseller News'', Microsoft Chairman Bill Gates stated that "Digital Research only exists to duplicate Microsoft operating systems." However, a lawsuit over Microsoft practices related to DR-DOS and CP/M-86 led to a $150,000,000 payment by Microsoft to Caldera Systems, who had bought the platform from Novell.
== Releases for CPC related == CP/M has a machine independent part which is provided by Digital Research and a machine dependent version which was implemented by the vendor. In Amstrad's case this was implemented by Amstrad and Locomotive Software.
* [[CP/M|CP/M 2.2]]
* [[DR Draw]]
* [[DR Graph]]
* [[Dr. Logo]]
* [[Pascal MT|PASCAL MT+]]