Spacewar is considered to be the world’s first computer game. The game was originally written in 1962 by MIT student Steve Russell for the PDP-1, the first computer that used an electric typewriter as input and a converted largish oscilloscope as output. Spacewar was a simple game where two players were able to shoot missiles at each other’s spaceships. The goal was to hit the other player before being hit yourself.
“Who invented the first computer game?” is not a question with a simple answer. Most gamers would say “Pong”, in which players deflect a bouncing white square by moving a line-shaped paddle, was the first computer game.
However, the very first incarnation of Pong in 1958, christened Tennis for Two, cannot be considered a computer game because it was produced without a digital computer. William A. Higinbotham generated a screen image of a ball and paddle using an oscilloscope, an analog laboratory instrument commonly used to measure electrical current and voltage. The game was a fascinating sidenote to the history of electronic entertainment even though it wasn’t actually a computer game.
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Were there any computer games before the year 1958? If we look briefly back at the major milestones in the history of the computer (see Table 1), the answer should be quite obvious.
Table 1: Milestones in the history of the computer.
Year
1936
1942
1944
1946 ENIAC 1
1947/48 The Transistor
1951
1953
1954
1955
1958
Milestone
Z1
ABC
Harvard Mark I
UNIVAC
IBM 701
Description
First freely programmable computer.
Solved simultaneous equations.
50 feet long, 8 feet tall, and weighed 5 tons
20 000 vacuum tubes.
First commercial computer, able to pick presidential winners.
The first commercially successful general-purpose computer.
FORTRAN
ERMA
The integrated Circuit
The first succesful high level programming language.
The first bank industry computer.
As we see, none of those machines were a suitable platform for a successful computer game. A typical computer in those days was a collection of huge gray cabinets approachable only through the intercession of an operator.
In the specially built computer room, the operator set switches, pushed buttons, and examined panels of flashing lights, while his assistants attended various other devices. Conclusion: no computer games before 1958. But when the first one appear after that?
In early 1961 there were three 25-year-old students, J. Martin Graetz, Stephen Russell, and Wayne Witanen, working at Harvard University’s Littauer Statistical laboratory. Most of the time they ran statistics computations for various Harvard staff members with an IBM 704. In their spare time they read science fiction novels such as Sky-
lark of Space and Gray Lensman. They also watched really terrible movies from the Toho Film Studios, of which
Rodan and Gozilla are the best-known examples.
In the summer of 1961 Graetz went to work for Professor Jack B. Dennis, who was owned the TX-0, a transistored computer with a flexowriter, printer, tape reader and scope. Many of the users of TX-0 worked for professor Dennis
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or in the Artificial Intelligence (AI) Group and Graetz felt that he had joined the ranks of the real programmers.
The TX-0 had a few demonstration programs: bouncing ball, shape and dot drawing, and Tic-Tac-Toe. Last one is actually a game; so why isn’t it considered to be the world’s first computer game? Maybe it was too simple-minded.
In any case these demonstration programs were the ingredients for the world’s first game.
For all its homeliness, the TX-0 was still huge, had to be carefully tended, took special procedures to start up and shut down, and cost a lot of money to build. All this changed in the fall of 1961 when DEC’s PDP-1 was installed next door to the TX-0. The PDP-1’s operating system was the first to allow multiple users to share the computer simultaneously. It was also the first computer anyone could turn on anytime by flipping one switch, and it turned off in the same way. Nothing like that had ever been seen before. It was only a matter of time before somebody would think to use it for something like playing games.
Before the PDP-1 was installed Graetz, Russell, and Witanen used to have talks about what to do with it. They all knew that a good computer demonstration program should satisfy three criteria:
It should demonstrate as many of the computer’s resources as possible, and tax those resources to the limit.
Within a consistent framework, it should be interesting, which means every run should be different.
It should involve the onlooker in a pleasurable and active way.
In short, it should be a game. Once in their talks Witanen started to imagine about fighting spaceships when
Graetz and Russell shouted “SPACEWAR!” simultaneously. Now they had an idea, and the basic rules of the game developed quickly: two spaceships, each controlled by a set of console switches. The ships would have a supply of rocket fuel and a missile weapon. There would also be a hyperspace button for hopeless situations.
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By the end of 1961, all the elements were in place and everyone was requesting Russell to do something about the idea of Spacewar. By that time Graetz was in a different department at MIT. Witanen was an unlucky Army
Reservist called to active duty during the Berlin Wall panic in October (1961) and sadly he never got to participate in developing his own idea. The reason why Russell had done nothing to implement the game was that he was extremely lazy. If there was a chance to chicken out for one reason or another, he used it. The PDP-1 had only a few diagnostic and utility routines; there was no program library. One of Russell’s excuses was the lack of sine-cosine routine. After Alan Kotok came back from a trip to DEC headquarters with a sine-cousine routine, Russell had no excuses left, and he had to start implementing the game.
By February, the first version of the game was operating. There were just the two spaceships, a supply of rocket fuel and a missile weapon. Peter Samson from the AI Group was disappointed by Russell’s random stars in the game. So he encoded the entire night sky by using data from the American Ephemeris and Nautical Almanac. Dan
Edwards (also from the AI Group) felt that gravity should be involved somehow. The gravity star was added in the center of the screen and its gravity covered the whole space; no matter where the spaceship was, if it didn’t move, it was drawn into the sun and destroyed. The missiles were not affected by gravity because it would have taken too much of the computer’s limited resources.
While all this was going on, Graetz was working on the hyperspace button. The idea was that when everything else failed you could jump into the fourth dimension and disappear. The disappearing spaceship left behind a signature which looked like the movement of photons around an atom. In each jump the spaceship’s coordinates were scrambled so that the player would not know where the spaceship would reappear - it could even be in the middle of the sun. This feature was something that could be used, but not something one would want to use.
Spacewar was working perfectly when used from the switches on the console, except that the two players did not have the same visual view, due to a feature of the CRT. There was a constant threat to the equipment when two excitable players were playing the game at the same time. There was also a possibility to miss the torpedo switch and hit the start level switch. A separate control device was necessary, but joysticks were not available in 1962.
Alan Kotok and Robert A. Saunders implemented the first Spacewar control boxes by using wood, wires, and
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switch-board hardware. There was a switch for right-left rotaion, another switch for acceleration (pulled back) and hyperspace (pulled forward), and a button for a missile weapon on the control boxes.
By the end of April (1962) the game was almost complete, only a scoring facility was added to limit the duration of matches. The only further work was to make the game presentable for MIT’s annual Science Open House in
May 1962. A large screen laboratory CRT was connected to the computer to function as a slave display; it allowed more people to watch matches when two players were playing. The game was an instant success and copies started flowing to other PDP-1 owners and eventually even DEC got a copy. The engineers at DEC used it as a diagnostic program on every new PDP-1 before shipping it.
It was amazing that the original Spacewar managed to include so many features, given the limitations of the PDP-1 computer: 9KB of memory and clock speed of 200khz. Nowadays a typical home computer can have, for example,
512MB (55k times more than in PDP-1) of memory and clock speed of 2GHz (10k times more than in PDP-1).
Russell has said: “If I hadn’t done it, someone would’ve done something equally exciting if not better in the next six months. I just happened to get there first.”. I do not agree with this self-deprecating utterance. If he had not done it, who would have and when? If we glance a little at the history of games after Spacewar, we are able to understand what an important step the Spacewar actually was.
In 1962, University of Utah student Nolan Bushnell also received his first exposure to videogames, playing Space-
war in the university’s computer lab. Bushnell spent the next seven years trying to reproduce Spacewar on a smaller, less expensive computer, to make it available as a coin-operated game. When it was finally completed in
1971, Bushnell’s Spacewar variation Computer Space, was released by coin-op manufacturer Nutting Associates; but people found it too complicated. The public had never seen a videogame before and wasn’t ready for all the different controls Computer Space featured.
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Bushnell was disappointed by the failure of Computer Space, but remained convinced that videogames were marketable. He founded a company called Atari and hired Atari’s first engineer, Al Alcorn. Bushnell was dreaming of a car game but thought that young Alcorn wouldn’t be ready for that kind of demanding task. So Alcorn got started with a Tennis for Two clone and named it Pong. In 1972, the first Pong arcade machine was placed in Andy Capp’s bar in Sunnyvale, California. It was a huge success and the concept got many imitators and even a few official sequels worldwide. This may be why “Pong” is the obvious answer to the question about the first computer game, although it was not actually the first one.
J. M. Graetz (1981) The Origin of Spacewar.
Creative Computing magazine.
WWW-page, http:
//users.rcn.com/enf/lore/spacewar/spacewar.html
(07.02.2004).
Lasse Rautiainen (2002) Computer Games: History and Software process. Master’s thesis, University of Joensuu,
Department of Computer Science. WWW-page, http://cs.joensuu.fi/~lrauti/source/gradu.
pdf (07.02.2004).
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