1974
Gary Kildall creates the CP/M operating system

CP/M, was the first commercial operating system for microprocessor-based personal computers that provided access to a disk drive storage unit. Unlike other operating systems fof the time, it was written in a high-level language rather than in assembly language that would tie it to a specific computer. This meant that CP/M could run on many different computer systems.

Created by Gary Kildall, CP/M originally stood for Control Program/Monitor, but was later changed to Control Program for Microcomputers.

Kildall started his company, Digital Research, Inc. (DRI) in Pacific Grove, California to sell CP/M. From the mid-1970s to the mid-1980s it was a widely used operating system for personal microcomputers. Kildall himself said:

"CP/M was an instant success. By 1980, DRI had sold millions of copies of CP/M to manufacturers and end-users."

Related information:

• The Centre for Computing History: Gary Kildall
• Computer History Museum: Gary Kildall and the 40th anniversary of the birth of the PC Operating System.
• Computer History Museum: Gary Kildall's unpublished memoirs, titled Computer Connections

Image:

• IEEE Milestone plaque commemorating CP/M outside the former headquarters of DRI at 801 Lighthouse Avenue, Pacific Grove, California
  Credit: Computer History Museum