A ROM image, or simply ROM, is a computer file which contains a copy of the data from a read-only memory chip, often from a video games cartridge or from an arcade machine's main board. The term is frequently used in the context of emulation, whereby older games are copied to ROM files on modern computers and can, using a piece of software known as an emulator, be played on the newer computer.

ROM images are also used when developing for embedded computers. Software which is being developed for embedded computers is often written to ROM files for testing on a standard computer before it is written to a ROM chip for use in the embedded system. At present, this article deals mainly with the use of ROM in relation to emulation.


Legal Status of ROMs

ROMs themselves are not illegal per se. This section gives a general discussion of the legal status of ROMs as regards the various uses to which they may be put, though this should not be construed as legal advice.

Games owned by the user

In most countries, it is entirely legal for an individual to personally make backup copies of a game they own. Individuals may make backup copies for various reasons, perhaps as insurance against losing the game or as redundancy in the event that the original game's medium becomes unreadable. See the section on ROMs and Preservation.

Officially Licensed ROMs

It is, of course, legal to purchase a ROM image which has been licensed to you by the rights holder. For example, Atari now make 27 of their original arcade games available in ROM format which is compatible with the MAME emulator through the online ROM retailer Star ROMs.

Freely Licensed ROMs

The vast majority of computer & video games from the history of such games are no longer manufactured. As such, the copyright holders of some games have offered free licenses to those games, often on the condition that they be used only for non-commercial purposes. For example, two of the games emulated in MAME, Gridlee and Robby have been made available under such licenses. As such, they are made freely available from the MAME Home Page. More recent examples include Id Software's release of the source code to Doom, Quake, Quake II and Quake III Arena under the GPL.

Unlicensed ROMs

While some games which no longer make any profit fit into the category above, the vast majority are no longer available in any form. The legality of obtaining such games varies from country to country. Some countries have special exceptions in copyright laws or case law which permit (or discourage less) copying when an item is not available for legal purchase or when the copying is for non-commercial or research purposes, while other countries may make such practices firmly illegal. There is often a distinction drawn between distribution and downloading, with distribution being seen as the greater offence.


Some emulation enthusiasts state that ROM trading is legal with regard to games which are no longer commercially available since those games have been abandoned by their copyright holders so have become Abandonware. However, this concept has no legal basis. Copyrights, unlike Trademarks, can not become abandoned through lack of use.

Commercial Distribution

Commercial distribution of copyrighted games without the consent of the copyright holder is generally illegal in almost all countries, with those who take part in that activity being liable for both criminal and civil penalties.

Online auction sites, such as eBay have sometimes been used by sellers to sell unauthorised copies of games which are advertised as legitimate copies. Such sellers, in addition to violating copyright laws, may also be liable for prosecution for fraud and/or false advertising.


There have been few convictions and lawsuits related to ROM trading. Criminal convictions tend to be related to high-profile Warez groups which trade combinations of recent films and Computer Games. In contrast, the ROM scene tends to concentrate mostly on older games. Given the lack of continuing profit from most older games, the grievances of games companies rarely exceed sending a Cease and desist order which compels the recipient to stop distributing the copyrighted works in question. Many have argued that it would be irrational for a company to spend money prosecuting for games that they are no longer making profit from, as there would be no damages to speak of.

ROM Abbreviations

  1. (1) - Japan/Korea
  2. (4) - USA/Brazil NTSC
  3. [a] - Alternate
  4. (A) - Australia
  5. (ADAM) - Coleco Adam version
  6. [b] - Bad Dump
  7. (B) - Non-USA
  8. [BF] - GB Bung Fix
  9. (BS) - SNES BS ROMs
  10. [c] - Checksum
  11. [C] - GBC
  12. © - China
  13. (E) - Europe
  14. [f] - Fixed
  15. (F) - France
  16. (FC) - French Canadian
  17. (FN) - Finland
  18. (G) - Germany
  19. (GR) - Greece
  20. [h] - Hack
  21. (HK) - Hong Kong
  22. (I) - Italy
  23. (J) - Japan
  24. (K) - Korea
  25. [M] - NeoGeo Pocket - Mono Only
  26. (M#) - Multilanguage (# of Languages)
  27. (NL) - Netherlands
  28. (NP) - SNES Nintendo Power
  29. [o] - Overdump
  30. [p] - Pirate
  31. (PAL) - Atari Euro version
  32. (PC10) - Nintendo PlayChoice 10
  33. (PD) - Public Domain
  34. [S] - GB Super
  35. (S) - Spain
  36. (ST) - SNES Sufami Turbo
  37. (SW) - Sweden
  38. [t] - Trained
  39. [T] - Translation
  40. (U) - USA
  41. (UK) - UK
  42. (Unl) - Unlicensed
  43. (Unk) - Unknown country
  44. [x] - Bad Checksum
  45. [!] - Verified Good Dump
  46. (-) - Unknown country
  47. (###) - Checksum
  48. (??k) - ROM Size
  49. ZZZ_ - Unclassified
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