ROM image

A ROM image, or ROM file, is a computer file which contains a copy of the data from a read-only memory chip, often from a video game cartridge, or used to contain a computer's firmware, or from an arcade game's main board.

ROMs can be copied from the read-only memory chips found in cartridge-based games and many arcade machines using a dedicated device in a process known as dumping.

For most common home video game systems, these devices are widely available, examples being the Doctor V64, or the Retrode.

For instance, the GameCube uses non-standard 8 cm DVD-like optical media, which for a long time prevented games stored on those discs from being copied.

However, as early as 2000, hackers found a way to decrypt and dump the ROMs successfully, making them playable once again in a Neo Geo emulator.

This contained a heavy copy protection algorithm which was not broken until 7 years after the system's release in 1993.

[1] The full decryption algorithm was cracked in 2007 by Nicola Salmoria, Andreas Naive and Charles MacDonald of the MAME development team.

Alternatively, the game may simply attempt to overwrite critical program instructions, which if successful renders it unplayable.

Video game console emulators typically take ROM images as input files.

Due to this aging, there is a significant worry that many early computer and video games may not survive without being transferred to new media.

So, those with an interest in preservation are actively seeking older arcade and video games and attempting to dump them to ROM images.

[2][3] The trend towards mass digital distribution of ROM image files, while potentially damaging to copyright holders, may also have a positive effect on preservation.