auto alarm - An auto alarm, or a car alarm, is an electronic device installed in an automobile in an attempt to discourage theft of the car itself and all of it's contents. Auto alarms work by emitting a high-volume sound, which is usually a siren, klaxon, pre-recorded verbal warning, the vehicle's own horn, or a combination of any of these. When the conditions necessary for triggering the auto alarm are met the car will sound this alarm and also start flashing some of the vehicle's lights. Some auto alarms can notify the car's owner via a paging system and it can also interrupt various electrical circuits necessary for the car to start. Auto alarms should not be confused with immobilizers; although the purpose of both may be to cars from being stolen or vandalized, they operate in a different way. An immobilizer normally will not offer any audible or visual theft deterrence, and it does not require any additional input from the driver than a non-immobilizer car. Even with all of the technological advances continually upgrading the effectiveness of our auto alarm systems, professional car thieves are also continually discovering new ways to disable these auto alarms. For some thieves, manipulating auto alarm systems is a full-time job, and at the same time knowing this is a source of unease for car owners. The persistence of car thieves has turned auto theft into a billion-dollar industry. Every 25.5 seconds a car is stolen despite the different efforts we have to safeguard our vehicles with an auto alarm system or anti-theft device.