ROM

A computer industry acronym for “Read-Only Memory”, which is memory that cannot be altered once its initial contents have been written. (This may not always be strictly true; there are “Programmable Read-Only Memory” (PROM or EPROM) devices which can be re-written, but such usually involves removing them from the circuit and installing them in a special programming fixture.) ROM memory is frequently used in synths for information which is not expected to change, such as the operating system code and the factory presets; it is so used because once written it does not require power to retain its contents, and it is nearly invulnerable to electrostatic discharges and other adverse conditions that can upset the contents of RAM memory.