Read-only memory

The notion of read-only data can also refer to file system permissions. Read-only memory (usually known by its acronym, ROM) is a class of storage media used in computers and other electronic devices. Because data stored in ROM cannot be modified (at least not very quickly or easily), it is mainly used to distribute firmware (software that is very closely tied to specific hardware, and unlikely to require frequent updates).
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Noun
1. (computer science) memory whose contents can be accessed and read but cannot be changed
(synonym) ROM, read-only storage, fixed storage
(hypernym) memory, computer memory, storage, computer storage, store, memory board
(hyponym) CD-ROM, compact disc read-only memory
(classification) computer science, computing

A memory in which data, under normal conditions, can only be read. Synonym nonerasable storage.

<storage> (ROM) A type of data storage device which is manufactured with fixed contents. In its most general sense, the term might be used for any storage system whose contents cannot be altered, such as a gramophone record or a printed book; however, the term is most often applied to semiconductor integrated circuit memories, of which there are several types, and CD-ROM.
ROM is inherently non-volatile storage - it retains its contents even when the power is switched off, in contrast to RAM.
ROM is often used to hold programs for embedded systems since these usually have a fixed purpose. ROM is also used for storage of the lowest level bootstrap software (firmware) in a computer.
See also Programmable Read-Only Memory.
(1995-05-09)

ROM