# Game Boy

The Game Boy is a handheld game console developed by Nintendo, launched in the Japanese home market on April 21, 1989, followed by North America later that year and other territories from 1990 onwards. Following the success of the Game & Watch single-game handhelds, Nintendo developed the Game Boy to be more like a portable console, with interchangeable cartridges. The concept proved highly successful and the Game Boy became a cultural icon of the 1990s and early 2000s.
The Game Boy was designed by the Nintendo Research & Development 1 team, led by Gunpei Yokoi and Satoru Okada. The device features a dot-matrix display, a directional pad, four game buttons, a single speaker, and uses Game Pak cartridges. Its two-toned gray design included black, blue, and dark magenta accents, with softly rounded corners and a distinctive curved bottom-right edge. At launch, it was sold either as a standalone unit or bundled with games like Super Mario Land and Tetris.
Despite mixed reviews criticizing its monochrome graphics compared to competitors like the Sega Game Gear, Atari Lynx, and NEC TurboExpress, the Game Boy's affordability, battery life, and extensive game library propelled it to market dominance. An estimated 118.69 million units of the Game Boy and its successor, the Game Boy Color (released in 1998), have been sold worldwide, making them the fourth-best-selling system ever. The Game Boy received several redesigns during its lifespan, including the smaller Game Boy Pocket (1996) and the Game Boy Light (1998). It was succeeded by the Game Boy Advance in 2001. Sales of Game Boy variants continued until 2003.

## Development

The Game Boy was designed by Nintendo Research & Development 1 (R&D1), the team behind the Game & Watch handhelds and video games including Mario Bros. and Donkey Kong. However, early in development, deep disagreements arose between R&D1 division director Gunpei Yokoi and assistant director Satoru Okada. Yokoi envisioned a simpler device, akin to an advanced Game & Watch, while Okada strongly advocated for a more powerful device with interchangeable cartridges, like a portable version of the successful Nintendo Entertainment System (NES). Their differing visions led to frequent clashes, heated meetings and high tensions, with Okada ultimately convincing Yokoi to adopt his approach.
The project was codenamed "Dot Matrix Game" (DMG), reflecting its display technology, which contrasted with the segmented LCDs of the Game & Watch series, where each screen was pre-printed with a static overlay, limiting each device to a single game. The "DMG" initials later became part of the Game Boy's official model number: "DMG-01."
Initially, the team considered using a Ricoh-manufactured CPU, similar to the one used in the NES, for potential compatibility. However, the team at Nintendo Research & Development 2, working on the Super Nintendo Entertainment System, requested that they find another vendor, concerned that supporting both consoles would strain Ricoh’s resources. As a result, the Game Boy team opted for a less powerful CPU from Sharp Corporation which was bundled in a package deal that also included LCD screens.
Despite support from Nintendo president Hiroshi Yamauchi, many within the company remained skeptical of the project’s viability. Some employees even mockingly referred to it as DameGame (with dame (だめ) meaning "hopeless" in Japanese).
Sharp, which was approached to provide LCD screens, was also unconvinced of the Game Boy’s commercial potential. Concerned Sharp might not commit to supplying the displays, Nintendo reached out to the Citizen Watch Company, which was already producing LCD screens for portable televisions. Citizen was eager to participate, but Yokoi and Okada continued discussions with Sharp, and even showed the company a Game Boy mockup. Seeing the potential of the prototype, and unwilling to lose Nintendo as a client to Citizen, Sharp made a competitive offer for both the displays and the CPU and secured the contract.
Sharp initially proposed a twisted nematic (TN) display, but after seeing a prototype, Yamauchi rejected it for being too hard to see. In response, Sharp suggested a super-twisted nematic (STN) display, which offered better contrast and viewing angles but was more expensive. To offset costs, the team reduced the screen size, though by that point in development, it was too late to shrink the overall size of the console.
Within R&D1, Yokoi had long championed "lateral thinking with withered technology", a design philosophy which eschewed cutting-edge technology in favor of innovative use of mature technologies, which tended to be more affordable and reliable. Following this principle, the Game Boy was designed without a backlight and used a simple grayscale screen to reduce costs and maximize battery life, despite concerns about visibility and the lack of color. This approach was ultimately vindicated, as competing handhelds with full-color, backlit screens suffered from poor battery life, making the Game Boy the more practical choice for consumers.
In the early 1980s, Okada had worked on an electronic game from Nintendo called Computer Mah-jong Yakuman that allowed cable communication between two devices, he thought it would be possible to implement a similar feature in the Game Boy. Despite concerns within the team that the feature would be too difficult to use and thus a waste of resources, Okada pushed forward and developed the Game Link Cable technology himself. This effort led to the creation of the "battle" and "trade" gameplay features in the Pokémon series, first released in 1996.
A prototype Game Boy was unveiled in 1987 and later exhibited at multiple industry trade shows. The device incorporated a key design element developed by Yokoi and his team at R&D1 for its Game & Watch predecessor: the directional control pad, often referred to as the "D-pad." Yokoi had recognized that traditional joysticks might hinder the portability of handheld devices. As a result, he designed the D-pad – a flat controller that extends just slightly beyond the device's casing. A similar layout had been used on the NES, making it easier for owners to transition to the handheld. Yamauchi predicted that the console would achieve sales exceeding 25 million units in its initial three years, a claim that was regarded as bold at the time.
Nintendo's philosophy centered on the belief that the appeal of a gaming system was primarily determined by the quality of its games. With this in mind, Okada pushed to make development tools available for third-party developers, a shortcoming of the launch of the NES. R&D1 also developed Super Mario Land, a portable adaptation of the Super Mario Bros. game, intending it to be the flagship title for the Game Boy. However, Henk Rogers brought the Soviet Union-made game, Tetris, to the attention of Nintendo of America. Despite its simple graphics and lack of a well-known brand, Tetris's suitability for a handheld platform convinced Nintendo president Minoru Arakawa to port and bundle it with the Game Boy. As a result, Tetris was bundled with the Game Boy in every region except Japan on its release.
The Game Boy launched in Japan in April 1989, followed by North America in July and Europe in September 1990, backed by a US$10 million marketing campaign. Sales of the Game Boy and its successor models (including the Game Boy Color) continued until early 2003.

## Hardware

The Game Boy uses a custom system on a chip (SoC), to house most of the components, named the DMG-CPU by Nintendo and the LR35902 by its manufacturer, the Sharp Corporation.$^{:11}$
Within the DMG-CPU, the main processor is a Sharp SM83,$^{:15}$ a hybrid of the Intel 8080 and Zilog Z80 processors. It combines the seven 8-bit registers of the 8080 (omitting the alternate registers of the Z80) with the programming syntax and additional bit manipulation instructions of the Z80. The SM83 also includes new instructions optimized for operations specific to the Game Boy's hardware arrangement. It operates at a clock rate of 4.194304 MHz.$^{:12}$
The DMG-CPU also incorporates the Picture Processing Unit, essentially a basic GPU, that renders visuals using an 8 KB bank of Video RAM located on the motherboard.$^{:11}$ The display is a 2.5-inch (diagonal) reflective super-twisted nematic (STN) monochrome liquid-crystal display (LCD), measuring 47 millimeters (1.9 in) wide by 43 millimeters (1.7 in) high with a resolution of 160 pixels wide by 144 pixels high in a 10:9 aspect ratio. The screen displays four shades of grey/green.$^{:16}$
Additionally, the SoC includes a 256 byte "bootstrap" ROM which is used to start up the device, 127 bytes of High RAM that can be accessed faster (similar to a CPU cache), and the Audio Processing Unit, a programmable sound generator with four channels: a pulse wave generation channel with frequency and volume variation, a second pulse wave generation channel with only volume variation, a wave channel that can reproduce any waveform recorded in RAM, and a white noise channel with volume variation.$^{:79}$ The motherboard also contains a 8 KB "work RAM" chip providing storage for general operations.$^{:16}$
The Game Boy's physical controls include a D-pad (directional pad), four action buttons (labeled 'A', 'B', 'SELECT', 'START'), a sliding power switch with a cartridge lock to prevent accidental removal, along with volume and contrast dials on either side of the device.
The original Game Boy was powered internally by four AA batteries. For extended use, an optional AC adapter or rechargeable battery pack can be connected via a coaxial power connector on the left side. The right side also has a Game Link Cable port for connecting to up to four Game Boy devices for multiplayer games or data transfer. For sound output, the Game Boy includes a single monaural speaker and a 3.5 mm headphone jack that offered stereo sound.

### Technical specifications

| | Game Boy | Game Boy Pocket | Game Boy Light |
| Height | 148 mm (5.8 in) | 127.6 mm (5.02 in) | 135 mm (5.3 in) |
| Width | 90 mm (3.5 in) | 77.6 mm (3.06 in) | 80 mm (3.1 in) |
| Depth | 32 mm (1.3 in) | 25.3 mm (1 in) | 27 mm (1.1 in) |
| Weight | 220 g (7.8 oz) | 125 g (4.4 oz) | 138 g (4.9 oz) |
| Display | 2.5-inch reflective super-twisted nematic (STN) liquid-crystal display (LCD) | 2.5-inch film compensated STN (FSTN) LCD | 2.5-inch FSTN LCD with electroluminescent backlight |
| Screen size (playable) | 45.5 × 41.5 mm (1.79 × 1.63 in) | 47.5 × 42.5 mm (1.87 × 1.67 in) | 47 × 42 mm (1.85 × 1.65 in) |
| Resolution | 160 (w) × 144 (h) pixels (10:9 aspect ratio) | 160 (w) × 144 (h) pixels (10:9 aspect ratio) | 160 (w) × 144 (h) pixels (10:9 aspect ratio) |
| Frame rate | 59.727500569606 Hz | 59.727500569606 Hz | 59.727500569606 Hz |
| Color support | 2-bit, four shades of green: 0x0 0x1 0x2 0x3 | 2-bit, four shades of grey: 0x0 0x1 0x2 0x3 | 2-bit, four shades of grey: 0x0 0x1 0x2 0x3 |
| System on a chip (SoC) | Nintendo DMG-CPU (Sharp LR35902) | Nintendo CPU MGB | Nintendo CPU MGB |
| Processor | 4.194304 MHz Sharp SM83 (custom Intel 8080/Zilog Z80 hybrid, 8-bit) | 4.194304 MHz Sharp SM83 (custom Intel 8080/Zilog Z80 hybrid, 8-bit) | 4.194304 MHz Sharp SM83 (custom Intel 8080/Zilog Z80 hybrid, 8-bit) |
| Memory | On SoC: 256 B ROM, 127 B High RAMInternal: 8 KB RAM, 8 KB Video RAM | On SoC: 256 B ROM, 127 B High RAM, 8 KB Video RAMInternal: 8 KB RAM | On SoC: 256 B ROM, 127 B High RAM, 8 KB Video RAMInternal: 8 KB RAM |
| External: (in the game cartridge) up to 1 MB ROM, up to 128 KB RAM |||
| Power | Consumption: 70–80 mAhInternal: 4 × AA batteriesExternal: 0.7 W at 6 V DC from 3.5 mm × 1.35 mm coaxial connector | Consumption: 80–90 mAhInternal: 2 × AAA batteriesExternal: 0.7 W at 3 V DC from 2.35 mm × 0.75 mm coaxial connector | Internal: 2 × AA batteriesExternal: 0.6 W at 3 V DC from 2.35 mm × 0.75 mm coaxial connector |
| Battery life | Up to 30 hours | Up to 10 hours | Up to 20 hours (backlight off)Up to 12 hours (backlight on) |
| Sound | Channels: 2 pulse wave, 1 wave, 1 noiseOutputs: Built-in mono speaker, stereo 3.5mm headphone jack | Channels: 2 pulse wave, 1 wave, 1 noiseOutputs: Built-in mono speaker, stereo 3.5mm headphone jack | Channels: 2 pulse wave, 1 wave, 1 noiseOutputs: Built-in mono speaker, stereo 3.5mm headphone jack |
| I/O | Game Link Cable (8 kbit/s between up to 4 devices)$^{:28}$Game Boy Game Pak slot | Game Link Cable (8 kbit/s between up to 4 devices)$^{:28}$Game Boy Game Pak slot | Game Link Cable (8 kbit/s between up to 4 devices)$^{:28}$Game Boy Game Pak slot |
| Controls | 4-way D-padFour action buttons (A, B, Start, Select)Volume potentiometerContrast potentiometerPower switch | 4-way D-padFour action buttons (A, B, Start, Select)Volume potentiometerContrast potentiometerPower switch | 4-way D-padFour action buttons (A, B, Start, Select)Volume potentiometerContrast potentiometerPower switch |

### Revisions

The Game Boy continued to experience strong sales well into the 1990s, as popular games continued to increase interest in the handheld. This commercial success was something of a double-edged sword for Nintendo; the device was seen as aged, but the company was unwilling to abandon it. Instead, the company embarked on a series of improvements to the Game Boy in an effort to keep the console relevant.

#### Play It Loud!

The first revision to the Game Boy came on March 20, 1995, when Nintendo released several special edition Game Boy models with colored cases, advertising them in the "Play It Loud!" campaign, known in Japan as Game Boy Bros. Play It Loud! units were manufactured in red, yellow, green, blue black, white, and clear (transparent). The Play It Loud's screens also have a darker border than the normal Game Boy.

#### Game Boy Pocket

A major revision to the Game Boy came in 1996 with the introduction of the Game Boy Pocket, a slimmed-down unit that required just two smaller AAA batteries, albeit at the expense of providing just 10 hours of gameplay. The other major change was that the screen was changed to a much-improved film compensated super-twisted nematic (FSTN) LCD. The screen's visibility and pixel response-time had been improved, mostly eliminating ghosting. Additionally, the film compensation layer produced a true black-and-white display, rather than the green hues of the original Game Boy. The Pocket also has a smaller Game Link Cable port, which requires an adapter to link with the original Game Boy. This smaller port design would be used on all subsequent Game Boy models. Internally, the Game Boy Pocket had a new SoC, the Nintendo CPU MGB, an improved version of the DMG-CPU. A major change was that the device's 8 KB of Video RAM was moved from the motherboard to the SoC for faster access.
The Game Boy Pocket was released in Japan on July 20, 1996, and in North America on September 2, 1996, for US$69.99 (equivalent to $140 in 2024). The Game Boy Pocket revitalized hardware sales and its release was ultimately well-timed as it coincided with the release of the first Pokémon game, which became a major hit and catapulted the aging Game Boy back into spotlight, spurring a new wave of sales. Reviewers praised the device's small size and improved display. However, other reviewers were dismissive of the device, with the Los Angeles Times saying Nintendo was "repacking the same old black-and-white stuff and selling it as new."
The initial version came only in silver and did not have a power LED, which also served as a battery strength indicator for the device. A revision in early 1997 added a power LED, different case colors (red, green, yellow, black, gold metal, clear, and blue) and dropped the price to US$54.95 (equivalent to $108 in 2024). By mid-1998, just months before the Game Boy Color went on sale, the price had fallen to US$49.95 (equivalent to $96 in 2024).

#### Game Boy Light

The Game Boy Light was a Japan-only revision released on April 14, 1998, just six months before the Game Boy Color. The Game Boy Light was priced at ¥6,800 (equivalent to ¥6,892 in 2019). The Game Boy Light is slightly bigger than the Game Boy Pocket and features an electroluminescent backlight allowing it to be played in low-light conditions. It uses two AA batteries, which give it approximately 12 gameplay hours with the backlight on and 20 with it off. It was available in two standard colors: gold and silver.

## Games

More than 1,000 games were released for the Game Boy, excluding cancelled and unlicensed games. Additionally, more than 300 games developed for the Game Boy Color were backward compatible with the monochrome Game Boy models.
Games are stored on cartridges called the Game Boy Game Pak, using read-only memory (ROM) chips. Initially, due to the limitations of the 8-bit architecture of the device, ROM size was limited to 32 KB. However, Nintendo overcame this limitation with a Memory Bank Controller (MBC) inside the cartridge. This chip sits between the processor and the ROM chips. The CPU can only access 32 KB at a time, but the MBC can switch between several banks of 32 KB ROM. Using this technology, Nintendo created Game Boy games that used up to 1 megabyte of ROM. Game Paks could also provide additional functionality to the Game Boy system. Some cartridges included up to 128 KB of RAM to increase performance, which could also be battery-backed to save progress when the handheld was off, real-time clock chips could keep track of time even when the device was off and Rumble Pak cartridges added vibration feedback to enhance gameplay.$^{:299}$
The top-selling franchise for the Game Boy were Pokémon Red, Blue, and Yellow, the first installments of the Pokémon video game series, which sold more than 46 million copies. The best-selling single game was Tetris, with more than 35 million copies shipped, it was a pack-in game included with the purchase of many original Game Boy devices.

### Launch titles

When the Game Boy was released in Japan in April 1989 alongside four launch titles: Alleyway (a Breakout clone), Baseball (a port of the NES game), Super Mario Land (an adaptation of the Mario franchise for the handheld format) and Yakuman (a Japanese mahjong game). When the console was introduced in North America, two more launch titles were added: Tetris and Tennis (another NES game port), while Yakuman never saw a wide international release.

## Reception
### Critical reception

Though it was less technically advanced than the Sega Game Gear, Atari Lynx, NEC TurboExpress and other competitors, notably by not supporting color, the Game Boy's lower price along with longer battery life made it a success. In its first two weeks in Japan, from its release on April 21, 1989, the entire stock of 300,000 units was sold; a few months later on July 31, 1989, 40,000 units were sold in the US on its release day there. It sold one million units in the United States within weeks. More than 118.69 million units of the Game Boy and Game Boy Color combined have been sold worldwide, with 32.47 million units in Japan, 44.06 million in the Americas, and 42.16 million in other regions. By Japanese fiscal year 1997, before Game Boy Color's release in late 1998, 64.42 million units of the Game Boy had been sold worldwide. At a March 14, 1994, press conference in San Francisco, Nintendo vice president of marketing Peter Main answered queries about when Nintendo was coming out with a color handheld system by stating that sales of the Game Boy were strong enough that it had decided to hold off on developing a successor handheld for the near future.
In 1995, Nintendo of America announced that 46% of Game Boy players were female, which was higher than the percentage of female players for both the Nintendo Entertainment System (29%) and Super Nintendo Entertainment System (14%). In 2009, the Game Boy was inducted into the National Toy Hall of Fame, 20 years after its introduction.
The console received mixed reviews from critics. In a 1997 year-end review, a team of four Electronic Gaming Monthly editors gave the Game Boy scores of 7.5, 7.0, 8.0, and 2.0. The reviewer who contributed the 2.0 panned the system due to its black-and-white display and motion blur, while his three co-reviewers praised its long battery life and strong games library, as well as the sleek, conveniently-sized design of the new Game Boy Pocket model.

### Sales

The Game Boy, Game Boy Pocket and Game Boy Color were commercially successful, selling a combined 118.69 million units worldwide: 32.47 million in Japan, 44.06 million in the Americas, and 42.16 million in all other regions. At the time of its discontinuation in 2003, the combined sales of the Game Boy made it the best-selling game console of all time. In later years, its sales were surpassed by the Nintendo DS, PlayStation 2 and Nintendo Switch, making it the fourth-best-selling console of all time, as of 2024.