CP/M
A disk operating system created in 1974 by Gary Kildall that became the standard for 8-bit business microcomputers.
Gary Kildall of Digital Research created CP/M in 1974 for Intel 8080-based microcomputers. It organizes files on a magnetic disk and loads and runs programs stored there.
Early versions ran one program at a time on 8-bit processors with no more than 64 kilobytes of memory. Later versions added multi-user variations and moved to 16-bit processors.
Why it matters
CP/M became the dominant operating system for microcomputers and was widely used in business from the late 1970s into the mid-1980s. It cut the work needed to move a program to a new maker's computer, which grew the market for hardware and software.
Key facts
- Created in 1974 by Gary Kildall.
- Made for Intel 8080-based microcomputers.
- Limited to 64 kilobytes of memory at first.
- Dominant in business into the mid-1980s.
- Made programs easier to port between computers.
Sources
- Wikipedia, "CP/M", en.wikipedia.org/wiki/CP/M, accessed October 14, 2026.
- Wikipedia, "Digital Research", en.wikipedia.org/wiki/Digital_Research, background reading, accessed October 14, 2026.