Spacewar! was conceived in 1961 by Martin Graetz, Stephen Russell, and Wayne Wiitanen. It was first realized on the PDP-1 in 1962 by Stephen Russell, Peter Samson, Dan Edwards, and Martin Graetz, together with Alan Kotok, Steve Piner, and Robert A Saunders. Spacewar! is in the public domain, but this credit paragraph must accompany all distributed versions of the program.

This is the original version! Martin Graetz provided us with a printed version of the source. We typed in in again - it was about 40 pages long - and re-assembled it with a PDP-1 assembler written in PERL. The resulting binary runs in a PDP-1 emulator written in JavaScript. The code is extremely faithful to the original. There are only two changes. 1)The spaceships have been made bigger and 2) The overall timing has been special cased to deal with varying machine speeds.

The sources are available in

The older Java version is in a subdirectory called "java".

The "a", "d", "s", "w" keys control one of the spaceships. The "j", "l", "k", "i" keys control the other. The controls are spin one way, spin the other, thrust, and fire.

Barry Silverman
Brian Silverman
Vadim Gerasimov