The History of Spacewar!: The Best Waste of Time in the History of the Universe

[In the latest in a series of Gamasutra-exclusive bonus material originally to be included in Bill Loguidice and Matt Barton's new book Vintage Games: An Insider Look at the History of Grand Theft Auto, Super Mario, and the Most Influential Games of All Time, we look at Spacewar!, one of the most groundbreaking games ever created. Previously in this 'bonus material' series: Elite, Tony Hawk's Pro Skater, Pinball Construction Set, Pong, and Rogue.]

If you're at all interested in the history of video games -- as any reader of this site must surely be -- then you've likely wondered what the first video game was like. What was, in fact, the first true video game to grace a screen?

This question has long plagued those of us who'd write even semi-accurate histories of the medium. Many gamers (and even some writers!) think the honor belongs to Pong (see bonus chapter, "Pong: Avoid Missing Game to Start Industry"), which introduced video games to the masses in the 1970s.

However, Pong wasn't even the first commercial arcade video game; it was preceded by Nolan Bushnell's and Ted Dabney's Computer Space for Nutting Associates, which had crashed on the launch pad in 1971.[1] As we'll see, Computer Space was itself based on a much earlier video game called Spacewar!, which was introduced in playable form as early as February 1962. Even Spacewar! had its antecedents; two frequently brought up games are OXO (1952) and Tennis for Two (1958).

The original Spacewar! code running on a PDP-1 emulator in a web browser. Shown here is the standard starting position.

The short answer to the question of what came first is that we don't know -- yet. The problem is that we only know of the games that were successful enough to be remembered by those who played or created them, and at least some of those people have to be interested and willing to tell their stories (with some sort of supporting evidence). Who knows how many pioneering games might simply have been forgotten?

The previous examples, for instance, gave the lie to earlier claims that Spacewar! had been first, and it's quite possible that as more and more people grow interested in the subject, we'll uncover still earlier and lesser-known games. There is, in short, no better time to be a game historian.

But even if Spacewar! isn't the first, it is certainly one of the first that really mattered. It was Spacewar! that established many of the conventions that are still with us today. Its influence on later developers was -- if not always successful -- quite palpable.

Even though Computer Space failed, Atari's later Asteroids (1979), offering similar gameplay concepts in a more user-friendly format, was a shattering success. We can also easily see Spacewar!'s influence in other popular video games like Atari's Lunar Lander (1979) and Gravitar (1982), and, if we tilt our eyes a bit, even in video game pinball simulations.

Spacewar! introduced real-time action, an arsenal of weapons, special moves, variable game conditions, physics, and a virtual world. It demonstrated that computers were far more than just expensive calculators. They were, at least for many of us, the future of entertainment.

Since early computer history and Spacewar!'s development were described in the Pong chapter, we'll simply provide a quick recap before going into detail about the game itself. The story of Spacewar!'s creation has been told many times, and we'd certainly point readers to Steven Levy's book Hackers: Heroes of the Computer Revolution for an in-depth look at not only the development of the game, but also the unique subculture that made it possible.

To put it simply, the creators of Spacewar! were the nerds that movies like Jeff Kanew's Revenge of the Nerds (1984) portrayed so humorously -- endlessly fascinated with science fiction, robots, electronic gadgets, and, of course, computers.

A Spacewar! battle under way.

[1] There is also some contention that Computer Space wasn't even the first coin-operated video game; that honor may belong instead to Bill Pitts and Hugh Tuck's Galaxy Game, another game inspired by Spacewar! that launched a few months before Computer Space. However, this game was not mass-produced, mostly because it was powered by a Digital PDP-11/20 minicomputer -- and a single unit cost over $20,000!

The creators of Spacewar! were students and faculty at MIT, which by the 1960s was highly invested in computer science and engineering. The computers of these days were clunky, room-sized behemoths, but MIT had acquired a DEC PDP-1, a much smaller machine (but still the size of three full-size refrigerators).

MIT had also had the good sense to acquire real display monitors and keyboards for its computers. Most computers at this time were limited to punch card readers for input and a printer for output; obviously this setup would make any sort of action game implausible.

DEC had a much different philosophy than the long-supreme IBM Corporation. IBM's vision of the computing industry was that individual users or "clients" would have nothing to do with the actual machine; they would take cards, programs, or tasks to designated operators (often sarcastically referred to as "priests"), who would be the only ones to physically interact with the computer.

The idea was that a corporation or university would contract with IBM for its computing services, whose own employees would handle the day-to-day computer operations. This model had made a great deal of sense in the early days of computers, when only highly trained professionals could operate and maintain them.

DEC saw things differently; individual users should be able to use and program their computers themselves. IBM's philosophy might be compared to a passenger train system; anyone could ride, but its professional engineers were the only ones authorized to operate (or even see) the engine, much less determine routes. DEC was more interested in selling "cars"; once you had one, you could go wherever you wanted and do whatever you wanted to with it. Eventually, DEC's approach would lead to the "user-friendly" hardware and software we enjoy today.

The nerdy members of MIT's Tech Model Railroad Club quickly adopted the PDP-1, spending the bulk of their days studying and writing programs or, "hacks," one of many new words they coined to describe their activities. Though most of these programs consisted of neat math or geometry tricks, Steve "Slug" Russell -- by all accounts something of a slacker -- decided to one-up his friends by designing a fully interactive science fiction game.

Russell's project might have sounded overly ambitious, but members of the Tech Model Railroad Club weren't the type to back down from a challenge. Russell's friends offered him a steady stream of encouragement and helped him stay on track however they could. Far from the secretive and highly competitive world of modern software development, Russell worked in what is now called an "open source" environment, where most code was freely shared and implemented without fear of copyright or patent infringement.

One such addition was Pete Sampson's "expensive planetarium" hack, which replaced the game's random backdrop of stars with an actual star field as seen from Earth. Like modern open source projects, Spacewar! would be routinely hacked and modified as individual programmers or groups saw fit to tack on new features.

When it was finally finished, Spacewar! was an impressive feat indeed. Two players controlled one of two spaceships that circled a small star with powerful gravity. The object of the game was to destroy the opponent's ship with a missile, being careful not to get sucked into the star's gravitational field.

Players could also enter hyperspace, which randomly relocated them somewhere else on the screen. This feature, of course, shows up in the much later Defender (which will be discussed in an upcoming bonus chapter, "Defender: The Joys of Difficult Games"), which also shared similarities with much of the rest of Spacewar!'s control options. Players controlled the game by flipping four switches, but this cumbersome control scheme was quickly replaced with custom boxes that ranged from prototypical game pads to joysticks.

Although Spacewar! would undoubtedly have appealed to many people besides the brilliant minds at MIT, its steep hardware requirements severely limited its availability. Only college students, and probably engineering students at that, had much chance to see and play these early video games. Nevertheless, development of ports and modifications continued throughout the 1970s, including Silas Warner's[2] Orbitwar (1974), which let players fight it out in networked bouts on the pioneering mainframe-based PLATO instructional system.

At the beginning of the 1970s, the arcade industry was limited to pinball and other electromechanical games, and home video game consoles and personal computers really wouldn't get off the ground until much later in the decade. Bushnell, the man who would later found Atari, was an electrical engineer who had played Spacewar! during his computer science studies at the University of Utah until his graduation in 1968.

Bushnell had also worked at Lagoon Amusement Park at Salt Lake City while he was home from school. Like most amusement parks then and now, Lagoon Amusement offered all sorts of challenging games that required a fee to play. It wasn't long before Bushnell began brainstorming ways to bring the geeky magic of Spacewar! to the masses -- and make a huge stack of money in the process.

Bushnell teamed up with a friend named Ted Dabney and began work on a cheap, coin-operated version of Spacewar!. As microprocessors weren't readily available, the two had to work with bulkier TTL (transistor-transistor logic) digital circuits. They built a futuristic cabinet for the game out of fiberglass, and stuck in a modified General Electric 15" black-and-white television for the display[3].

Even if the game itself wasn't very fun to play, the cabinet looked so exotic that Richard Fleischer used it as a prop in his science fiction film, Soylent Green (1973), which is set in the year 2022! Calling themselves Syzygy, the two had to work long hours repairing broken pinball machines to survive as they sought out a manufacturer for Computer Space. They finally settled on Nutting Associates, who made electromechanical arcade machines.

Computer Space, released November 1971, was far from an exact clone of Spacewar!. It did not, for instance, feature either two-player combat or a gravity well. Instead, a single player controlled a rocket in open space, dodging enemy fire and trying to destroy two computer-controlled flying saucers.

The game was difficult to control, and even though an estimated 1,500 units of a two player version were built with enhanced control panels[4], the game didn't enjoy the mass appeal that Bushnell had hoped for. As the story goes, Bushnell became convinced that a simpler game would have a better shot at success, an insight that led him to develop Pong. However, Computer Space's unimpressive sales might owe more to its lackluster gameplay than the ignorance or incompetence of players.

Screenshot from Cinematronics' Space Wars.

[2] For more on Silas Warner, see book Chapter 2, "Castle Wolfenstein (1981): Achtung! Stealth Gaming Steps out of the Shadows".

[3] http://marvin3m.com/arcade/cspace.htm.

[4] See http://www.klov.com/game_detail.php?game_id=7381 for more information on the different versions.

Bushnell and Dabney weren't the only ones to try to market a coin-operated version of Spacewar!. A more successful effort came in 1977 with Larry Rosenthal's Space Wars. Rosenthal had been a student at MIT where the original game had been developed, and felt that he could do a better job than the earlier efforts at converting it for arcades. However, he demanded a full 50% of the profits, and only the floundering Cinematronics was willing to accept his demands.

Rosenthal's key innovation was developing a special processor, which was cheap to make yet still sophisticated enough to run the full version of Spacewar!, complete with the gravity well and two-player dog fighting that made the original so compelling. It also offered other innovations, such as the ability to take some damage before exploding. Players could adjust the gravity and inertia of the game world as well. Gameplay was strictly time-based; whoever had the most kills at the end of the match won the game.

Perhaps the game's most important feature was its vector-based graphics, which made it both more faithful to the original and better-looking than Computer Space's raster graphics had been.

The essential difference between vector and raster graphics is that the former are based on lines instead of dots or pixels. Vector graphics tended to look much sharper than the raster games of the era. In the end, it was a wonderful adaptation of Spacewar! and earned rich profits for Rosenthal and Cinematronics.

In 1978, Atari released Orbit, yet another raster-based adaptation of Spacewar!. Unlike the previous effort, however, this one at least offered two-player side-by-side play out-of-the-gate and borrowed the partial damage system of Space Wars.

Perhaps the only really interesting aspect of the game is that the ships now looked like the Enterprise and a Klingon Bird of Prey from Star Trek. The game wasn't a hit and is rarely spoken of today, though a simplified home version for the Atari 2600 VCS was released in 1978: Space War.

Screenshot from Atari's Orbit.

Box back from one of the many early home games that took inspiration from Spacewar!, Fairchild's Space War (1977) for their Video Entertainment System.

Atari went vector skelter in 1979 with Lunar Lander (also discussed in book Chapter 8, "Flight Simulator (1980): Digital Reality") and Asteroids, two stunningly innovative but notoriously difficult games. Lunar Lander, as the name implies, had players carefully landing a lunar module on one of several moon bases (platforms, really).

What made the game so challenging was its painfully realistic physics: players had to work hard to generate just enough thrust to maneuver the lander and resist gravity. Fuel was at an absolute premium; running out meant almost certain death.

This game was eventually ported and cloned on home platforms; former Commodore VIC-20 owners may remember the clone Jupiter Lander (1981), for instance. The gameplay concepts introduced in Lunar Lander would later evolve into the many "gravity" and "thrust" games of the 1980s, including Atari's aforementioned Gravitar in 1982.

Screenshot from Atari's Gravitar.

Lyle Rains's and Ed Logg's Asteroids offered a terrific innovation that fundamentally altered Spacewar!'s gameplay concepts. Instead of blasting a rival space pilot, Asteroids had players destroying huge asteroids. Every time an asteroid was hit, it splintered into pieces, any one of which would destroy the player's ship in a collision. As with Spacewar!, players could hit a button to zoom into hyperspace, but might reappear in an even more dangerous situation than before. Asteroids was a huge success for Atari, and has been ported, cloned, and modified ever since.

Screenshot for XYPE's 2003 release of Thrust+ PlatinumThrust+ for the Atari 2600 Video Computer System. Platinum featured both gravity effects and momentum as critical components of its gameplay. 

Despite the success of Asteroids and Space Wars, enthusiasm for this style of game seemed to ebb soon after the introduction of Taito's Space Invaders in 1978 (see book Chapter 16, "Space Invaders (1978): The Japanese Descend").

Space Invaders gobbled up far more quarters than any of the old gravity-and-thrust games, which suggested that realistic physics wasn't all that important to most gamers.

Soon enough, games that required players to deal with complex issues of inertia and momentum were pushed to the dustier corners of the arcade.

A simulated view of a worse-for-the-wear Asteroids arcade machine.

Then again, we might see Spacewar!'s influence on other types of games that greatly benefited from accurate physics. This influence is perhaps most keenly felt in the simulation genres, particularly with flight simulators (book Chapter 8) and racing games (book Chapter 14, "Pole Position (1982): Where the Raster Meets the Road"). However, it's also the driving principle behind virtual pinball games (bonus chapter, "Pinball Construction Set: Launching Millions of Creative Possibilities").

Clearly, all of these types of games have relied heavily on complex "physics engines" to make their gameplay feel more like the real thing. We're also starting to see more and more discussion of physics in the first- and third-person shooter genres (book Chapter 5, "Doom (1993): The First-Person Shooter Takes Control").

It's no longer acceptable for such a game to show the same bloody mess every time the player shoots an enemy, for instance. If the enemy is hit at point-blank range with a shotgun, it ought to go flying back, perhaps bouncing off a wall or two before finally settling down to wallow in its puddle of blood.

Screenshot from Midway's Omega Race from 1981, with simulated color backdrop. Omega Race was an interesting mix of elements from Spacewar! and Asteroids in an enclosed environment.

Spacewar!'s ultimate contribution however, might be its depiction of a virtual world. Although some might argue that even a tic-tac-toe or tennis game features some sort of virtual world, we don't necessarily agree.

We should understand the difference between a game surface, such as a tennis court or chessboard, and a game world, such as the outer space environment of Spacewar! or one of the islands of Myst (book Chapter 12, "Myst (1993): Launching Multimedia Worlds").

Though we could easily get bogged down in theoretical discussions of "navigable space" and "habitable environments," suffice it to say that Spacewar! introduced gamers and developers to the notion that computers could represent and let players explore coherent virtual worlds, not just simulate simple motions in abstract space.

You didn't just play with these toys; you played in them. Though later games would of course dramatically refine the concept, it should be clear enough that even with Spacewar! we see lavish attention paid to defining the game world and making it feel realistic -- even going so far as to offer a realistic star map!

As the name so profoundly suggests, Spacewar! isn't about Xs and Os on a board, but a war in (navigable) space. For many computer scientists and engineers accustomed to seeing computers as nothing but expensive tabulating machines, it must have been a revelation to see Spacewar! for the first time. No doubt a few of them might have wondered, "What have we done?" while waiting impatiently for a turn. Steve "Slug" Russell had given us space.

[NOTE: For further reading, Gamasutra has also published a history of Spacewar! written by Game Developer magazine's Jeff Fleming, covering the game from a more first-person perspective, thanks to an interview with game co-creator J.M. “Shag” Graetz.]