The Master System, while far from being Sega's first 8-bit game console, was notably their first foray into the international gaming market, released in 1986 in response to the launch of the Nintendo Entertainment System in North America.
Realizing that the SG-1000 was too antiquated to compete with Nintendo's Family Computer on a global scale (the SG-1000 was essentially identical to the ColecoVision and the original MSX, as they were all built from common shelf parts), Sega significantly upgraded the console's technical capabilities for its third iteration. Released on October 1985, this new version of the console was dubbed the Sega Mark III and featured a slightly faster CPU and an upgraded video display processor over previous models (bringing it on par with both the Famicom and the MSX2), while having backwards compatibility with all legacy SG/SC series software and peripherals. Cosmetically the Sega Mark III hardware was very similar to the SG-1000 II, aside from the addition of a built-in card slot, meaning that it could play games in so-called MyCard format (which required a separately sold Card Catcher adapter on SG-1000 consoles) in addition to traditional cartridges, as well as different placement for the controller ports (which were moved from the rear to the front) and the power switch (which was placed from the front to the back).
In the same way the Famicom became the NES outside Japan, the Sega Mark III was heavily redesigned for its export version (codenamed the "Mark IV"), receiving a black casing that would become a trademark for all subsequent Sega platforms (at least in the west) up until the Dreamcast. The console was originally marketed as the Sega Video Game System in North America (and simply referred as the Sega System in technical documentations) and was initially sold in two bundles: the "Sega Base System" and the "Sega Master System". Despite this, all the consoles produced had "Master System/Power Base" printed on them, regardless of the bundle purchased, and even the system's BIOS referred to the platform as the Master System, which is how it became the standardized name. The Mark III would be relaunched in Japan in 1987 with the Master System name and styling, and also with a built-in FM sound chip (never included in the export versions and sold separately as an add-on for the Mark III) to enhance the quality of chiptunes, along with a rapid fire switch instead of a reset button.
All things considered, the Master System was more advanced than the NES on a surface level, although the NES was able to keep up thanks to the inclusion of memory mappers in later game cartridges that expanded the hardware's capabilities. Ultimately, Sega failed to wrestle away the majority of the market share away from Nintendo due to their stranglehold on third party developers with their strict exclusivity policy. The unfortunate timing of the PC Engine's launch in Japan, with its graphical capabilities that blew away both the Famicom and the Mark III, didn't help matters, which forced Sega to come up with a new system that could succeed the Master System and compete adequately with the emerging 16-bit generation: the Mega Drive, otherwise known as the Genesis in North America.
The Mark III/Master System was discontinued in early 1989 in Japan, a few months after the launch of its successor in the end of 1988. It lasted only a few more years in the United States as a budget-priced alternative to the Genesis in the form of the redesigned Master System II (aka "Mark IV Jr."), before being discontinued in 1991. However, it did gain a lot of ground in Europe, Oceania and South America, especially in Brazil, where it was still receiving new titles by the mid-to-late '90s (including a version of Street Fighter II). The Master System's popularity in the UK in particular was helped by a bungled distribution effort from Nintendo which meant that the NES was so rare in Britain as to be practically mythical (mainly because for the UK, Ireland, Italy, Spain, Portugal, Australia and New Zealand, Mattel of all companies was in charge of marketing and distribution— perhaps remembering their own console attempt not having done so well, they were determined to see Nintendo sunk like they were); the NES did manage to outsell the Master System in Australia, if by only a small margin.
Although Sega's own series didn't really gain ground until the Mega Drive, their popular Phantasy Star series got its start here. Their handheld, the Game Gear, uses hardware quite comparable with the Master System, which facilitated the development of ports and multiplatform releases on both platforms. In fact, converters exist that allow Master System games to be played on the Game Gear and vice-versa.
- The CPU: Zilog Z80A note , runs at 3.55 or 3.58 MHz, depending on the region.
- The graphics are handled by the Video Display Processor, a modified version of the TI 9918/9928 GPU MSX and Coleco also used.
- Eight kilobytes of main Random Access Memory with 16 KB of Video RAM. Games like Phantasy Star really showed all this memory off.
- Game ROM sizes ranged from 8 KB (Snail Maze) to 1MB (Virtua Fighter Animation).
- Like the NES, SMS sprites are 8x8 or 8x16 pixels, with up to 64 on screen.
- Resolution was 256x224 pixels.
- 32 colors were allowed on screen, out of 64 total.
- Video is obtainable through an RF modulator, composite cables, or SCART/JP-21 cables, and can be modded for S-Video support. The Master System II only supports RF and composite, but can be modded for RGB and S-Video. What makes the Master System unique is that its AV outlet is a standard RGB port rather than a proprietary design, meaning that it's possible to plug in any old SCART cable rather than having to buy specially designed ones; this trait would be carried over to the Sega Genesis.
- The system's basic sound functionality included three square wave channels, a noise generator and a DPCM channel. This was the only area in which the Master System's hardware was noticeably inferior to that of the NES, lacking a triangle channel and any of the nifty hardware effects that the NES could apply to music and sound effects, although it was still way ahead of what the Atari 7800 had to offer.
- That is unless you lived in Japan, where an FM Sound Unit could be purchased separately as an add-on for the Mark III, which connected into the console's expansion port, enhancing the sound quality of all compatible titles (over 40 released in Japan). The add-on employs a Yamaha YM2413 sound chip, which is very similar to the YM2612 later used by the Genesis/Mega Drive, adding nine extra sound channels that provided a superior sound quality over most Famicom/NES games (in turn, the only Famicom cartridge to output FM audio was Konami's Lagrange Point, which utilized a customized mapper). Unfortunately the add-on was never released in the west due to the omission of the expansion port from the Master System redesign of the console, although the Japanese MK-2000 model has the Yamaha chip built into the hardware to compensate for this. An FM Sound Unit can still be installed into a western console through modding.
- Due to the abrupt discontinuation of the Mark III/Master System in Japan, certain games that were programmed to be compatible with the FM Sound Unit ultimately ended up having overseas releases only, such as Ultima IV and OutRun 3D, thus the only way to enable FM sounds in these games (besides emulation) is through console modding or by playing them on a Japanese console with a converter. With Wonder Boy III: The Dragon's Trap in particular, the game will only enable FM sounds when played on a Japanese console.
- Japanese and South Korean cartridges used a 44-pin connector, whereas cartridges in other regions (the Americas and Europe) used a 50-pin connector. The 44-pin connector in the Japanese and Korean consoles made them backwards compatible with all SG-1000/SC-3000 cartridges. However, SC-3000 specific cartridges (which consisted of educational and programming software) are not fully compatible with the Japanese Master System due to the lack of expansion port required to plug in the SK-1100 keyboard, which the Mark III did have. Japanese Mark III/Master System cartridges can be play on a western console with a converter, but not SG-1000/SC-3000 cartridges (due to the western consoles not having the required SG-1000 BIOS). Japanese Mark III cartridges were released in two lineup, first party Gold Cartridges, comprising almost the entirety of the system's cartridge library with the exception of two titles published by Salio (a dummy branch of Tecmo), which were labelled Silver Cartridges.
- The Sega MyCard format (called "Sega Cards" outside Japan) was very similar to the HuCard format later employed by NEC and Hudson Soft for the PC Engine, in which games were sold in small credit card sized IC chips that were smaller and easier to produce than cartridges. In fact, the first year of Mark III software in Japan consisted almost entirely of MyCard releases, as its first "Gold Cartridge" game (Fantasy Zone) came out almost a year after the console was launched. However, the vast majority of the MyCard games in Japan were actually developed to be compatible with SG-1000 hardware through the Card Catcher cartridge add-on, and only a handful of MyCards (15 to be exact) were designed to run exclusively on the Mark III. By the time the Master System was launched in North America, Sega was already phasing out MyCards and going back to traditional cartridges that could hold more ROM space. The card slot was ultimately removed from the Master System II redesign of the console (consequently rendering the SegaScope 3D glasses incompatible as well) and many Sega Card games ended up being reissued in cartridge format in Europe.
- Aleste (aka Power Strike)
- Alex Kidd in Miracle World (and several sequels)
- Ghost House
- Land of Illusion
- The Lucky Dime Caper
- Master of Darkness
- Phantasy Star
- Psycho Fox
- Sonic the Hedgehog Chaos
- Wonder Boy III: The Dragon's Trap
- Zaxxon 3-D
Ported, Reformulated, or Concurrently Developed
- After Burner
- Alien Storm
- Alien Syndrome
- Altered Beast
- Baku Baku Animal
- Bonanza Bros.
- Bubble Bobble
- Captain Silver
- Castle of Illusion
- Chuck Rock
- Cool Spot
- Desert Strike
- Double Dragon
- Dynamite Dux
- Dynamite Headdy
- Earthworm Jim
- Ecco the Dolphin
- Fantastic Dizzy
- Fantasy Zone
- Férias Frustradas do Pica-Pau
- Fire and Ice
- Gain Ground
- Ghouls 'n Ghosts
- Golden Axe
- Heroes of the Lance
- Impossible Mission
- Jurassic Park
- King's Quest
- Laser Ghost
- The Lion King
- Marble Madness
- Michael Jackson's Moonwalker
- Montezuma's Revenge
- Mortal Kombat
- Ms. Pac-Man
- The New Zealand Story
- Ninja Gaiden (a standout reformulation)
- Operation Wolf
- Prince of Persia
- Psychic World
- Road Rash
- RoboCop Versus The Terminator
- Seishun Scandal
- Sensible Soccer
- Shadow of the Beast
- The Simpsons: Bart vs. the Space Mutants
- The Simpsons: Bart vs. the World
- The Smurfs
- Solomon's Key
- Sonic the Hedgehog (reformulated from the 16-bit version)
- Space Harrier
- Spy vs. Spy
- Street Fighter II
- Streets of Rage 1 & 2
- Super Smash T.V.
- Ultima IV
- Virtua Fighter Animation
- Where in the World Is Carmen Sandiego?
- Wonder Boy
- Xenon 2 Megablast
- Xevious (actually an unlicensed version called MICRO XEVIOUS)
- Ys: The Vanished Omens
- Damn You, Muscle Memory!: One of the strangest design elements of the console is that the controller has no pause button—the pause switch is located on the console itself!
- Follow the Leader: The Master System tried hard to play catch up to the NES in the US. Even the controller is identical to an NES pad, albeit without a start or select button.
- Germans Love David Hasselhoff: Despite being unable to dethrone the NES in North America, the system still lives on in Brazil, where plug-and-play variations of the console are still being sold to this day by Tectoy, Sega's representative in the region. As a matter of fact, the Master System is so popular in the country that it even rivaled recent consoles such as the PlayStation 4 in terms of units sold, and that conversions of titles like Street Fighter II and games based on local franchises such as Monica's Gang were made to appeal to local tastes. It makes sense considering how it's way less expensive than newer systems, coupled with Nostalgia Filter by Brazilians who grew up playing games on the Master System.
- Moe Anthropomorphism: There is a Sega Hard Girls representative for the console. She is very well-liked in Brazil and the rest of South America, referencing the console's own popularity in that continent.
- Product Facelift: The Sega Master System II considerably slimmed down the console into a minuscule size. All versions of the latter came with in a built-in game of some kind, be it Alex Kidd In Miracle World or the 8-bit Sonic the Hedgehog.