Codex Gamicus

Space Invaders (スペースインベーダー Supēsu Inbēdā?) is an arcade video game designed by Tomohiro Nishikado and released in 1978. It was originally manufactured and sold by Taito in Japan, and was later licensed for production in the United States by the Midway division of Bally.

Space Invaders was a widely popular arcade game, and still holds it's place today as one of the most beloved and most played arcade games. Space Invaders legacy has spanned decades after it's original 1978 release, being ported to dozens of platforms, including online video game stores such as Xbox Live Arcade and more. Space Invaders had a major impact on the Arcade market and video games in general, and was one of the earliest examples of successful Japanese arcade machines.

The game was released in Japan by Taito in June 1978,[5] followed by a limited North American release by Taito America in July 1978.[6] It was then given a wide North American release by Midway in October 1978,[7] and Midway then released it in Europe in 1978.[8] It was released in Australia by Leisure & Allied Industries, also in 1978.[9]


Space Invaders is one of the earliest shooting games and the aim is to defeat waves of aliens with a laser cannon to earn as many points as possible. In designing the game, Nishikado drew inspiration from popular media: Breakout, The War of the Worlds, and Star Wars. To complete it, he had to design custom hardware and development tools.

The game runs on the Taito 8080 arcade system board.

It was one of the forerunners of modern video gaming and helped expand the video game industry from a novelty to a global industry (see golden age of video arcade games). When first released, Space Invaders was very successful.

The game has been the inspiration for other video games, re-released on numerous platforms, and led to several sequels. The 1980 Atari 2600 version quadrupled the system's sales and became the first "killer app" for video game consoles. Space Invaders has been referenced and parodied in multiple television shows, and been a part of several video game and cultural exhibitions. The pixelated enemy alien has become a pop culture icon, often used as a synecdoche representing video games as a whole.



Space Invaders pits your space ship, three lives, and four destroyable shields against an onslaught of aliens from above that only get faster. You manoeuvre from left to right, shooting enemies, while taking cover underneath your shields. The shields can be destroyed by the enemy shots, or by you yourself. While shooting through your own shields gives you more openings to hit the aliens, it also puts your ship at risk.

The enemies gradually come down until they reach the bottom. The more you kill, the faster they move. Eventually, when there is only one left, it will move at high speeds as it increases speed, drops down, and reverses direction.

As more aliens are defeated, the aliens' movement and the game's music both speed up. Defeating the aliens brings another wave that is more difficult, a loop which can continue without end.[5][10][11][12]

Occasionally, a mothership crosses the top of the screen, awarding the player points for hitting it. Although the point values are thought to be random, players of the arcade game have found out how to make the mothership award the maximum amount of points (300 points).

The game is somewhat unique in that it is essentially unwinnable.


Space Invaders was created by Tomohiro Nishikado, who spent a year designing the game and developing the necessary hardware to produce it.[13] The game's inspiration is reported to have come from varying sources, including an adaptation of the mechanical game Space Monsters released by Taito in 1972, and a dream about Japanese school children who are waiting for Santa Claus and are attacked by invading aliens. However, Nishikado has cited Atari's arcade game Breakout as his inspiration. He aimed to create a shooting game that featured the same sense of achievement from completing stages and destroying targets, but with more complex graphics.[13][14] Nishikado used a similar layout to that of Breakout, but altered the game mechanics. Rather than bounce a ball to attack static objects, players are given the ability to fire projectiles at their own discretion to attack moving enemies.

Early enemy designs included tanks, combat planes, and battleships. Nishikado, however, was not satisfied with the enemy movements; technical limitations made it difficult to simulate flying.[13][15] Humans would have been easier to simulate, but Nishikado considered shooting them immoral.[15][16] After seeing a magazine feature about Star Wars, he thought of using a space theme. Nishikado drew inspiration for the aliens from H. G. Wells' The War of the Worlds — he had watched the 1953 film adaptation as a child — and created initial bitmap images after the octopus-like aliens. Other alien designs were modelled after squids and crabs. The game was originally titled Space Monsters, inspired by a popular song in Japan at the time, but was changed to Space Invaders by Nishikado's superiors.


Because microcomputers in Japan were not powerful enough at the time to perform the complex tasks involved in designing and programming Space Invaders, Nishikado had to design his own custom hardware and development tools for the game. He created the arcade system board using new microprocessors from the United States.[14] The game uses an Intel 8080 central processing unit, and features raster graphics on a CRT monitor and monaural sound hosted by a combination of analogue circuitry and a Texas Instruments SN76477 sound chip.[2][16][17]

It also uses the Fujitsu MB14241 as a video shifter,[3] to accelerate the sprite drawing and bitmapping;[18] it uses frame buffer technology, rather than the tile-map technology later introduced by the Namco Galaxian hardware.[19] The Taito 8080 hardware designed for Space Invaders was later used by a number of other arcade games.[1][3]

Despite the specially developed hardware, Nishikado was unable to program the game as he wanted — the Control Program board was not powerful enough to display the graphics in colour or move the enemies faster — and he considered the development of the hardware the most difficult part of the whole process. While programming the game, Nishikado discovered that the processor was able to render the alien graphics faster the fewer there were of them on screen. Rather than design the game to compensate for the speed increase, he decided to keep it as a challenging gameplay mechanic.

Space Invaders was first released in a cocktail-table format with black-and-white graphics for the Japanese market.[11] There were then Japanese cocktail cabinets that used rainbow-colored cellophane strips in a variety of reds, blues, and purples,[11] such as T.T. Space Invaders in 1978.[20] It was followed by worldwide releases of an upright cabinet format, where the graphics are reflected onto a painted backdrop of a moon against a starry background. The Western upright cabinet release by Midway used strips of orange and green cellophane over the screen to simulate color graphics, which most of the Japanese upright cabinets lacked.[11] There were later Japanese cocktail cabinets that used full color display hardware.[11]

The cabinet artwork features large, humanoid monsters not present in the game. Nishikado attributes this to the artist basing the designs on the original title, Space Monsters, rather than referring to the in-game graphics.


Despite its simplicity, the music to Space Invaders was revolutionary in the gaming industry. Video game scholar Andrew Schartmann identifies three aspects of the music that would have a significant impact on the development of game music:

  1. Whereas video game music prior to Space Invaders was restricted to the extremities (i.e. a short introductory theme with game-over counterpart), the alien-inspired hit featured continuous music — the well-known four-note loop — throughout, uninterrupted by sound effects. "It was thus the first time that sound effects and music were superimposed to form a rich sonic landscape. Not only do players receive feedback related directly to their actions through sound effects; they also receive stimulus in a more subtle, non-interactive fashion through music".
  2. The music interacts with on-screen animation to influence the emotions of the player. "That seemingly pedestrian four-note loop might stir us in the most primitive of ways, but that it stirs us at all is worthy of note. By demonstrating that game sound could be more than a simple tune to fill the silence, Space Invaders moved video game music closer to the realm of art".
  3. The music popularized the notion of variability — the idea that music can change in accordance with the ongoing narrative. The variable in Space Invaders (tempo) is admittedly simple, but its implications are not to be underestimated. "Over the years, analogous strategies of variation would be applied to pitch, rhythm, dynamics, form, and a host of other parameters, all with the goal of accommodating the non-linear aspect of video games".

Space Invaders Deluxe[]

A sequel game called Space Invaders Deluxe (also Space Invaders Part II) was released in the arcades by Taito Corporation in 1979 and Midway Games in 1980. While similar in gameplay to the original, it deviates from it in a few small ways. First of all, there is the addition of a flashing UFO that crosses the top of the screen that is worth 500 points if you hit it when it's visible. Secondly, from the second wave on, some of the middle-row invaders will split into two smaller invaders. And thirdly, the mothership will appear in later levels to drop reinforcements into the advancing formation. It also includes an intermission scene between waves where one of the invaders flees to the top of the screen, calling out SOS! SOS! SOS!


  • Alien in bottom two rows ("skull") - 10 points
  • Alien in middle two rows ("toaster") - 20 points
  • Alien in top row ("conehead") - 30 points
  • Mystery ship — 50 to 300 points, depending on how many shots have been fired between appearances
  • Flashing mystery ship in Space Invaders Deluxe — 200 or 500 points, depending on the chip set being used (Midway or Taito)

Atari 2600 version[]

The Atari 2600 version of Space Invaders is one of the most successful arcade-to-home ports ever made and released for the system. While simplified in some aspects (there are only 36 invaders to deal with, you have only 3 shields to hide behind, and the mother ship is always 200 points), it is made up for in the multitude of game player variations, such as:

  • Moving Shields: the player's shields move back and forth.
  • Zigzagging Bombs: the invaders' bombs drop in a zigzagging pattern.
  • Fast Bombs: the invaders' bombs drop faster.
  • Invisible Invaders: the invaders only show up briefly when you hit one of them.
  • One Player: your standard one-player game.
  • Two Players Alternating: your standard two-player game, when each player takes turns.
  • Two Players Competing: both players play at the same time, shooting at the same group of invaders. Here the game ends when either both players lose three laser bases among them or the invaders land.
  • Two Players Competing, Alternating Shots: same as Two Players Competing, except that each player takes turns firing. If a player takes too long to fire, his laser base automatically fires a shot.
  • One Player Moves Left, Other Player Moves Right: the left player can only move the laser base to the left, the right player can only move it to the right. Either player can fire.
  • Players Alternate Control: the left player moves the laser base until he fires a shot, then the right players has control until he fires a shot, and so on.
  • One Player Moves, Other Player Fires: the left player moves the cannon, the right player fires.

By using the difficulty switches, the player(s) can select to choose a small laser base (B setting) or a wide laser base (A setting).

Reception, impact, and legacy[]

Review scores
Publication Score
Allgame Arcade: 5/5 stars[21]
Atari 2600: 5/5 stars[22]
Atari 5200: 4/5 stars[23]
SNES: 4/5 stars[24]
Entity Award
Arcade Awards Game of the Year[25]

After the first few months following its release in Japan, the game became very popular. Specialty arcades opened with nothing but Space Invaders cabinets, and by the end of 1978, Taito had installed over 100,000 machines and grossed over $600 million in Japan alone. Within two years by 1980, Taito had sold over 300,000 Space Invaders arcade machines in Japan, in addition to 60,000 machines in the United States, where prices ranged from $2000 to $3000 for each machine, within one year. The arcade cabinets have since become collector's items with the cocktail and cabaret versions being the rarest. By mid-1981, more than four billion quarters, or $1 billion, had been grossed from Space Invaders machines, and it would continue to gross an average of $600 million a year through to 1982, by which time it had grossed $2 billion in quarters (equivalent to $7.26 billion in 2022), with a net profit of $450 million (equivalent to $1.63 billion in 2022). This made it the best-selling video game and highest-grossing entertainment product of its time, with comparisons made to the then highest-grossing film Star Wars Episode IV: A New Hope, which had grossed $486 million in movie tickets (costing $2.25 each on average) with a net profit of $175 million. Space Invaders had earned Taito profits of over $500 million.

An oft-quoted urban legend states that there was a shortage of 100-yen coins — and subsequent production increase — in Japan directly attributed to the game,[13][26][27] although in actuality, 100 yen coin production was lower in 1978 and 1979 than in previous or subsequent years. The claim also doesn't hold up to logical scrutiny; arcade operators would have emptied out their machines and taken the money to the bank, thus keeping the coins in circulation. Reports from those living in Japan at the time indicate "nothing out of the ordinary ... during the height of the Space Invaders invasion".

The 1980 Atari 2600 version was the first official licensing of an arcade game and became the first "killer app" for video game consoles by quadrupling the system's sales. It sold over two million units in its first year on sale as a home console game, making it the first title to sell a million cartridges. Other official ports of the game were made for the Atari 8-bit computer line and Atari 5200 console. Taito released it for the Famicom in 1985. Numerous unofficial clones were made as well, such as the popular computer games Super Invader (1979) and TI Invaders (1981).

Game designer Shigeru Miyamoto considered Space Invaders a game that revolutionized the video game industry; he was never interested in video games before seeing it. Hideo Kojima also described it as the first video game that impressed him and got him interested in video games. Several publications ascribed the expansion of the video game industry from a novelty into a global industry to the success of the game. Edge Magazine attributed the shift of video games from bars and arcades to more mainstream locations like restaurants and department stores to Space Invaders. Its popularity was such that it was the first game where an arcade machine's owner could make up for the cost of the machine in under one month, or in some places, within one week.

Technology journalist Jason Whittaker credited the game's success to ending the video game crash of 1977, which had earlier been caused by Pong clones flooding the market, and beginning the golden age of video arcade games. According to The Observer, the home console versions were popular and encouraged users to learn programming; many of whom later became industry leaders. stated that Space Invaders showed that video games could compete against the major entertainment media at the time: films, music, and television. IGN attributed the launch of the arcade phenomenon in North America in part to Space Invaders. Electronic Games credited the game's success as the impetus behind video gaming becoming a rapidly growing hobby and as "the single most popular coin-operated attraction of all time". Game Informer considered it, along with Pac-Man, one of the most popular arcade games that tapped into popular culture and generated excitement during the golden age of arcades. IGN listed it as one of the "Top 10 Most Influential Games" in 2007, citing the source of inspiration to video game designers and the impact it had on the shooting genre. ranked it at No. 3 in its list of "The 60 Most Influential Games of All Time", stating that, in contrast to earlier arcade games which "were attempts to simulate already-existing things", Space Invaders was "the first video game as a video game, instead of merely a playable electronic representation of something else". In 2008, Guinness World Records listed it as the top-rated arcade game in technical, creative, and cultural impact.

As one of the earliest shooting games, it set precedents and helped pave the way for future titles and for the shooting genre.[28][29] Space Invaders popularized a more interactive style of gameplay with the enemies responding to the player controlled cannon's movement, and was the first video game to popularize the concept of achieving a high score,[5][26][28] being the first to save the player's score. While earlier shooting games allowed the player to shoot at targets, Space Invaders was the first in which targets could fire back at the player. It was also the first game where players were given multiple lives, had to repel hordes of enemies, could take cover from enemy fire, and use destructible barriers, in addition to being the first game to use a continuous background soundtrack, with four simple diatonic descending bass notes repeating in a loop, which was dynamic and changed pace during stages, like a heartbeat sound that increases pace as enemies approached.

It also introduced the concept of a difficulty curve, with the aliens moving faster as the player kills more of them, making the game more difficult as it progresses. The game's concept of scaling difficulty became the basis for modern single-player video gaming. [1]

It also moved the gaming industry away from Pong-inspired sports games grounded in real-world situations towards action games involving fantastical situations. Whittaker commented that Space Invaders helped action games become the most dominant genre on both arcades and consoles, through to contemporary times. Guinness World Records considered Space Invaders one of the most successful arcade shooting games by 2008. In describing it as a "seminal arcade classic", IGN listed it as the number eight "classic shoot 'em up". Space Invaders set the template for the shoot 'em up genre. Its worldwide success created a demand for a wide variety of science fiction games, inspiring the development of arcade games, such as Atari's Asteroids, Williams Electronics' Defender, and Namco's Galaxian and Galaga, which were modelled after the gameplay and design of Space Invaders. This influence extended to most shooting games released to the present day, Doom, Halo and Call of Duty. Space Invaders also had an influence on early computer dungeon crawl games such as Dungeons of Daggorath, which used similar heartbeat sounds to indicate player health.

Space Invaders' concept of a gradually increasing difficulty level also revolutionized the gaming industry.[30] According to Retro Gamer, by "giving birth to the multi-billion-pound global industry" Space Invaders is "directly responsible for the existence of the Gran Turismo, Metal Gear Solid, Tomb Raider and Final Fantasy series."[11]

Remakes and sequels[]

Space Invaders has been remade on numerous platforms and spawned many sequels. Re-releases include ported and updated versions of the original arcade game. Ported versions generally feature different graphics and additional gameplay options—for example, moving defence bunkers, zigzag shots, invisible aliens, and two-player cooperative gameplay. Ports on earlier systems like the Atari home consoles featured simplified graphics, while later systems such as the Super Nintendo Entertainment System and PlayStation featured updated graphics. Later titles include several modes of gameplay and integrate new elements into the original design. For example, Space Invaders Extreme, released on the Nintendo DS and PlayStation Portable, integrated musical elements into the standard gameplay. A spin-off for WiiWare, Space Invaders Get Even, allows players to control the aliens instead of the laser cannon.

In 1980, Bally Midway released a pinball version of the game. However, few elements from the original game are included, and the aliens instead resembled the xenomorphs from the film Alien; Bally Midway was later sued over the game's resemblance to designs by H. R. Giger. Different ports have been met with mixed receptions; the Atari 2600 version was very successful while the Nintendo Entertainment System version was poorly received.

Taito has released several arcade sequels that built upon the basic design of the original. The first was Space Invaders Part II in 1979; it featured colour graphics, an attract mode, and new gameplay elements, and added an intermission between gameplay. According to the Killer List of Video Games, this was the first video game to include an intermission. This version was released in the United States as Deluxe Space Invaders (also known as Space Invaders Deluxe), but featured a different graphical colour scheme (just yellow and green rather than the full color of Part II) and a lunar-city background. Another arcade sequel, titled Space Invaders II, was released exclusively in the United States. It was in a cocktail-table format with very fast alien firing and a competitive two-player mode. During the summer of 1985, Return of the Invaders was released with updated colour graphics, and more complex movements and attack patterns for the aliens.[11] Subsequent arcade sequels included Super Space Invaders '91, Space Invaders DX, and Space Invaders '95. Each game introduced minor gameplay additions to the original design. Like the original game, several of the arcade sequels have become collector's items, though some are considered rarer. In addition, Atari released a rare Atari 2600 version of the game called Pepsi Invaders in 1983, endorsed by The Coca-Cola Company.[11] In 2002, Taito released Space Raiders, a third-person shooter reminiscent of Space Invaders.

The game and its related games have been included in video game compilation titles. Space Invaders Anniversary was released in 2003 for the PlayStation 2 and included nine Space Invader variants. A similar title for the PlayStation Portable, Space Invaders Pocket, was released in 2005. Space Invaders, Space Invaders Part II and Return of the Invaders are included in Taito Legends, a compilation of Taito's classic arcade games released in 2005 on the PlayStation 2, Xbox, and PC. Super Space Invaders '91, Space Invaders DX and Space Invaders '95 were included in Taito Legends 2, a sequel compilation released in 2006.

Popular culture[]


A pixelated alien graphic used at the concert event Video Games Live

Many publications and websites use the pixelated alien graphic as an icon for video games in general, including video game magazine Electronic Gaming Monthly, technology website Ars Technica, and concert event Video Games Live.

The game—and references to it—has appeared in numerous facets of popular culture. Soon after the game's release, hundreds of favourable articles and stories about the emerging video game medium popularized by Space Invaders aired on television and were printed in newspapers and magazines. The Space Invaders Tournament held by Atari in 1980 was the first video game competition and attracted more than 10,000 participants, establishing video gaming as a mainstream hobby. The Arcade Awards ceremony was created that same year to honour the best video games, with Space Invaders winning the first Game of the Year award.[25] The impact of Space Invaders on the video game industry has been compared to that of The Beatles in the pop music industry. Considered "the first blockbuster video game", Space Invaders became synonymous with video games worldwide for some time.

Within a year of the game's release, the Japanese PTA unsuccessfully attempted to ban the game for allegedly inspiring truancy. In North America, doctors identified a condition called the "Space Invaders elbow" as a complaint, while a physician in The New England Journal of Medicine named a similar ailment the "Space Invaders Wrist." Space Invaders was also the first game to attract political controversy, when a 1981 Private Member's Bill called the "Control of Space Invaders (and other Electronic Games) Bill" drafted by British Labour Party MP George Foulkes attempted to ban the game for its "addictive properties" and for causing "deviancy"; a motion to bring the bill before Parliament was briefly debated but defeated by 114 votes to 94 votes – the bill itself was never considered by Parliament.


Musicians drew inspiration for their music from Space Invaders. Video Games Live performed audio from the game as part of a special retro "Classic Arcade Medley".

The pioneering Japanese synthpop group Yellow Magic Orchestra reproduced Space Invaders sounds in its 1978 self-titled album and its hit single "Computer Game", the latter selling over 400,000 copies in the United States.

Other pop songs based on Space Invaders soon followed, including disco records such as "Disco Space Invaders" (1979) by Funny Stuff, and the hit songs "Space Invader" (1980) by The Pretenders, "Space Invaders" (1980) by Uncle Vic and the Australian hit "Space Invaders" (1979) by Player One (known in the US as Playback), which in turn provided the bassline for Jesse Saunders' "On and On" (1984), the first Chicago house music track.

Space Invaders is referenced in the lyrics to Rush's 1981 hit song "Tom Sawyer," and the game is singled out for special thanks in the liner notes to the band's Permanent Waves album.<

The game was also sampled in I-F's "Space Invaders Are Smoking Grass" (1997), the first electroclash record.

In honor of the game's 30th anniversary, Taito produced an album titled Space Invaders 2008. The album is published by Avex Trax and features music inspired by the game. Taito's store Taito Station also unveiled a Space Invaders themed music video.


Multiple television series have aired episodes that either reference or parody the game and its elements; for example, Danger Mouse, That '70s Show, Scrubs, Chuck, and The Amazing World of Gumball.

Elements are prominently featured in the "Raiders of the Lost Arcade" segment of "Anthology of Interest II", an episode of Futurama.


In 2006, the game was one of several video game related media selected to represent Japan as part of a project compiled by Japan's Agency for Cultural Affairs.

In the same year, Space Invaders was included in the London Science Museum's Game On exhibition meant to showcase the various aspects of video game history, development, and culture.

The game is also a part of the Barbican Centre's traveling Game On exhibition.

At the Belluard Bollwerk International 2006 festival in Fribourg, Switzerland, Guillaume Reymond created a three-minute video recreation of a game of Space Invaders as part of the "Gameover" project using humans as pixels.

The GH ART exhibit at the 2008 Games Convention in Leipzig, Germany, included an art game, Invaders!, based on Space Invaders's gameplay. The creator later asked for the game to be removed from the exhibit following criticism of elements based on the September 11 attacks in the United States.

A French street artist known as Invader made a name for himself by creating mosaic artwork of Space Invader aliens around the world.

The British billionaire Richard Branson was a Space Invaders fan. [2]


An arcade-accurate homebrew port of both the original arcade game and its sequel Space Invaders Deluxe has been developed and released for the ColecoVision as Space Invaders Collection.

The Gameboy version which was released by Nintendo as a "Super Gameboy compatible" game has an unlockable Super NES version of the game that can be activated when it is played on a Super NES using the Super Gameboy.

See also[]


  1. 1.0 1.1 1.2 1.3 Taito 8080 Based Hardware. Retrieved on 2015-01-11
  2. 2.0 2.1 Space Invaders Videogame by Bally Midway (1978). Killer List of Videogames. Retrieved on May 12, 2008
  3. 3.0 3.1 3.2 8080bw. MAME. Retrieved on 2015-01-11
  4. Space Invaders at the Gaming-History database
  5. 5.0 5.1 5.2 Kevin Bowen. The Gamespy Hall of Fame: Space Invaders. GameSpy. Retrieved on January 27, 2010
  6. Space Invaders (Taito America) at the Gaming-History database
  7. Space Invaders (Midway) at the Gaming-History database
  8. European releases:
    Space Invaders (France). Retrieved on 2015-01-12
    Space Invaders (Germany). Retrieved on 2015-01-12
    Space Invaders (Spain). Retrieved on 2015-01-12
  9. Space Invaders (AU). Retrieved on 2015-01-12
  10. Craig Glenday, ed (March 11, 2008). "Top 100 Arcade Games: Top 5". Guinness World Records Gamer's Edition 2008. Guinness World Records. Guinness. p. 237. ISBN 978-1-904994-21-3. 
  11. 11.0 11.1 11.2 11.3 11.4 11.5 11.6 11.7 "The Definitive Space Invaders". Retro Gamer (Imagine Publishing) (41): 24–33. September 2007. 
  12. Seabrook, Andrea (April 12, 2008). Replay: the Evolution of Video Game Music. All Things Considered. National Public Radio. Retrieved on May 12, 2008
  13. 13.0 13.1 13.2 13.3 Staff (January 2008). "Classic GI: Space Invaders". Game Informer (Game Stop) (177): 108–109. 
  14. 14.0 14.1 Staff. "Nishikado-San Speaks". Retro Gamer (Live Publishing) (3): 35. 
  15. 15.0 15.1 Kiphshidze, N; Zubiashvili, T; Chagunava, K (October 2005). "The Creation of Space Invaders". Edge (Future plc) (154): 7–13. ISSN 1512-0112. PMID 18323584. Retrieved May 5, 2008. 
  16. 16.0 16.1 Edwards, Benj. Ten Things Everyone Should Know About Space Invaders. Archived from the original on 2009-02-26 Retrieved on July 11, 2008
  17. Morris, Dave (2004). The Art of Game Worlds. HarperCollins. p. 166. ISBN 0-06-072430-7. 
  18. Chris Cantrell. Arcade Space Invaders. Retrieved on 2015-01-12
  19. Mark J. P. Wolf (2012), Before the Crash: Early Video Game History, Wayne State University Press, p. 173, ISBN 0814337228,, retrieved 2015-01-12 
  20. T.T. Space Invaders at the Gaming-History database
  21. Weiss, Brett Alan. Space Invaders. AllGame. Retrieved on 3 November 2014
  22. Weiss, Brett Alan. Space Invaders. AllGame. Retrieved on 3 November 2014
  23. Weiss, Brett Alan. Space Invaders. AllGame. Retrieved on 3 November 2014
  24. Weiss, Brett Alan. Space Invaders. AllGame. Retrieved on 3 November 2014
  25. 25.0 25.1 "The Arcade Awards". Electronic Games 1 (1): 38–9. Winter 1981. Retrieved February 1, 2012. 
  26. 26.0 26.1 Craig Glenday, ed (March 11, 2008). "Record Breaking Games: Shooting Games Roundup". Guinness World Records Gamer's Edition 2008. Guinness World Records. Guinness. pp. 106–107. ISBN 978-1-904994-21-3. 
  27. Richards, Giles (July 24, 2005). A life through video games. The Observer. Guardian Media Group. Retrieved on May 22, 2008
  28. 28.0 28.1 Geddes, Ryan (December 10, 2007). IGN's Top 10 Most Influential Games. IGN. Retrieved on July 11, 2008
  29. Craig Glenday, ed (March 11, 2008). "Record Breaking Games: Shooting Games". Guinness World Records Gamer's Edition 2008. Guinness World Records. Guinness. p. 88. ISBN 978-1-904994-21-3. 

External links[]