Software stored in read-only memory (ROM) or programmable ROM (PROM). Easier to change than hardware but harder than software stored on disk. Firmware is often responsible for the behaviour of a system when it is first switched on. A typical example would be a "monitor" program in a microcomputer which loads the full operating system from disk or from a network and then passes control to it.
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Nearby terms: firewall machine « FireWire « fireworks mode « Firmware » firmy » first class module » First Fit