'CD-ROM' stands for "Compact Disc Read-Only Memory." A 'CD-ROM' is a compact disc (CD) that can be read by a computer with an optical drive. The "ROM" part of the term means the data on the disc is "read-only," that cannot be altered or erased.

During the 1990s, 'CD-ROMs' were popularly used to distribute software and data for computers and fourth generation video game consoles. Some 'CDs', called enhanced 'CDs', hold both computer data and audio with the latter capable of being played on a 'CD player', while data (such as software or digital video) is only usable on a computer.

The 'CD-ROM' format was developed by Japanese company Denon in 1982. It was an extension of Compact Disc Digital Audio, and adapted the format to hold any form of digital data.

Because of this feature and their large capacity, 'CD-ROMs' are a great media format for retail software. 'CD-ROMs' share the same technology as audio 'CDs', but they are formatted differently, allowing them to store many types of data.

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