ROM chips are soldered or socketed right into the circuitry of your computer. Each ROM chip has a circuit path that allows a processor -- either the CPU or a secondary processor somewhere else in the system -- to access the read-only memory on that chip.

Processors look up the instructions on ROM chips when they need directions on how to perform certain functions that rarely change.

The bottom line is that ROM is mostly a "hands off" technology that average computer users don't need to worry about. But if you're going to try to upgrade the basic input/output system (BIOS) on an EEPROM or Flash ROM chip, be careful: The BIOS on these chips varies among manufacturers. Each type of upgrade is only compatible with a specific system design. Put in the wrong instructions and you risk blowing the motherboard.

If you don't know exactly what you're doing, get expert help.