Computer systems that cannot be programmed by the user because they are preprogrammed for a specific task and are buried within the equipment they serve. The term derives from the military, where computer systems are generally activated by the flip of a switch or the push of a button. For example, a military aircraft pilot may wish to turn on the countermeasures equipment with a switch. There is no need for the pilot to be involved with the computer. The same holds true for a soldier who may direct a ground-to-ground missile against a target tank by the push of a button. In both cases, an embedded computer quickly goes to work.