PDP-8

PDP-8
A PDP-8 on display at The National Museum of Computing in Bletchley, England. This example is from the first generation of PDP-8s, built with discrete transistors and later known as the Straight 8.
DeveloperDigital Equipment Corporation
Product familyProgrammed Data Processor
TypeMinicomputer
ReleasedMarch 22, 1965 (1965-03-22)
Introductory priceUS$18,500, equivalent to about $189,000 in 2025
Units sold50,000+
PlatformPDP 12-bit
PredecessorPDP-5
SuccessorPDP-12

The PDP-8 is a family of 12-bit minicomputers that was produced by Digital Equipment Corporation (DEC). Launched in 1965, it was the first minicomputer to sell for under $20,000, and the $25,000 mark for a complete system would later be a defining characteristic of the minicomputer class. Over 50,000 units were sold during the model's lifetime.

Its basic design follows the pioneering LINC but has a smaller instruction set, which is an expanded version of the PDP-5 instruction set. To lower the cost of implementation, the system leaves out a number of commonly used functions which have to be written using combinations of other instructions. This leads to complex programs.

The PDP-12 is an offshoot of the PDP-8 with a processor that can run programs for the PDP-8 and LINC systems. The successor to the PDP-8 line is the PDP-11, which featured a much more complete instruction set and was not backward compatible.