PDPs at universities
For about fifteen years, the DEC PDP line was the working medium of academic computing. Cheap enough for a single department and interactive enough to sit at, the PDPs became the machines on which an extraordinary amount of foundational software was first written. Time-sharing, Unix, Lisp and artificial intelligence, interactive graphics, the whole hacker culture, all of it has a PDP somewhere near its origin. Spacewar! on MIT's PDP-1 is the first of these, and far from the last.
Which PDP, and what it produced
| Site | Machine(s) | From | What came off it |
|---|---|---|---|
| MIT (TMRC, RLE) | PDP-1 | 1961 | Spacewar! (1962), early time-sharing experiments, and the Tech Model Railroad Club hacker culture |
| MIT (Project MAC / AI Lab) | PDP-6 → PDP-10 | mid-1960s | ITS (the Incompatible Timesharing System), MacLisp and Macsyma, the origins of Emacs; the AI Lab formed in 1970 |
| Stanford (SAIL) | PDP-1 → PDP-6/10 | 1964 | Raj Reddy's first speech recognition under John McCarthy on the PDP-1; the Stanford AI Lab on the PDP-6/10 |
| Cambridge (UK) | PDP-7 + Type 340 | 1966 | Duel (c.1968), a two-player Spacewar!-style game on a vector display |
| Bell Labs | PDP-7 → PDP-11 | 1969 | The birth of UNIX (Ken Thompson, 1969) and then C (Dennis Ritchie, 1971–73), with Unix rewritten in C on the PDP-11 |
| UC Berkeley | PDP-11/45 → VAX | 1974 | The BSD line of Unix; 3BSD (1979) with virtual memory, on the early VAX |
| University of Utah | DEC machines | late 1960s | The Sutherland and Evans computer-graphics group, foundations of 3D graphics (the exact DEC model is not firmly recorded) |
| Carnegie Mellon | PDP-10 | 1970s | Raj Reddy's continuous speech recognition (Hearsay, Harpy and the line toward Sphinx) under the DARPA speech programme |
Bell Labs is a research laboratory rather than a university, included here because the PDP-7 and PDP-11 work done there is important in relation to research work. The exact DEC model at Utah, and the precise machine behind each CMU speech system, are not confirmed.
The medium of a generation's computing
It is hard to overstate how much of modern computing was first written on these machines. The PDP line was not a backdrop to this work; it was its medium, the constitutive ground on which time-sharing, Unix, Lisp and interactive graphics became thinkable and then real. Spacewar! belongs to the very start of that story, the moment a roomful of students discovered that an interactive computer was a thing you could do something playful and expressive with.
References
- Computer History Wiki (gunkies.org), the ITS and per-model pages; Wikipedia's History of Unix and ITS.
- On Cambridge's Duel, the Kinephanos study "Space Odyssey"; see also our Cambridge page.
- On Reddy, the ACM A.M. Turing Award profile; and our media-machine page.