DEC machines

[#] DEC WWW server.
[#] PDP Page by Stephane Tsacas.
[#] Various DEC FAQs.
[#] PDP archive at


(this section was contributed by Doug Jones [])

It's worth noting that the PDP-8/S was the first computer offered for retail sale, on a cash and carry basis. This was in 1968, when the PDP-8/S was the least expensive computer in the world, priced at $20,000, and a small number of people began to purchase 8/S systems as personal computers. Continuing until around 1975, various models of the PDP-8 continued to be the most popular personal computer in the world (with a total penetration into the home market that must have been very small).

[#] PDP-8 WWW page.
[#] History of the PDP-8 architecture.
[#] PDP-8 programming and general information.
[#] PDP-8 archive at
[#] archive.
[#] PDP-8 software at


PDP-10 is the machine that made timesharing real. It looms large in hacker folklore because of its adoption in the mid-1970s by many university computing facilities and research labs, including the MIT AI Lab, Stanford, and CMU. Some aspects of the instruction set (most notably the bit-field instructions) are still considered unsurpassed. The 10 was eventually eclipsed by the VAX machines (descendants of the PDP-11) when DEC recognized that the 10 and VAX product lines were competing with each other and decided to concentrate its software development effort on the more profitable VAX. The machine was finally dropped from DEC's line in 1983, following the failure of the Jupiter Project at DEC to build a viable new model.

[#] PDP-10 archive at


(Provided by Megan Gentry [], John Wilson [], and other people)

The PDP-11 was, and is an extremely successful and influential family of machines which was spanned in two decades from the early 1970s to the early/mid 1990s.

[#] PDP-11 FAQ list.
[#] PDP-11 archive at
[#] PDP-11 software at
[#] PDP-11 software at


The most famous computer that never was. PDP-10 computers running the TOPS-10 operating system were labeled `DECsystem-10' as a way of differentiating them from the PDP-11. Later on, those systems running TOPS-20 were labeled `DECSYSTEM-20' (the block capitals being the result of a lawsuit brought against DEC by Singer, which once made a computer called `system-10'), but contrary to popular lore there was never a `PDP-20'; the only difference between a 10 and a 20 was the operating system and the color of the paint. Most (but not all) machines sold to run TOPS-10 were painted `Basil Blue', whereas most TOPS-20 machines were painted `Chinese Red' (often mistakenly called orange).