Over the years, automotive security systems have advanced considerably. Perhaps the newest addition to these systems is the Global Positioning System (GPS) tracking unit, which makes use of orbiting satellites to pinpoint you to the location of your car in case it gets stolen. With this system installed in your car, you can be alerted when your car is moving without you in it. Because it makes use of GPS, you will be able to see the position of your car and check on your security options in real time (through the Web). In some systems, you can even toggle with door locks and stop the engine from the Web or using your cell phone. Because car thieves do not seem to be deterred with just car alarms, it's always good to have an "extra" security system, something that can help you recover your car in case it gets stolen. Not to mention that it is an effective way of keeping track of your teen-ager’s car. Perhaps the downside in a GPS tracking unit is that it requires line-of-sight access – the car should be "seen" by the satellite, in which case obstructions such as parking garages hide your car from view.

An alternative to a GPS tracking unit, which at this time still costs a lot, is radio transceivers. The most common system of this kind is the LoJack Vehicle Recovery System, which is used by law enforcement agencies to track and recover stolen vehicles. The method of tracking is quite easy. The radio transceiver is first installed in the vehicle and its unique code registered in the law enforcement agencies' database. In the event of a theft, you report the incident to the police who matches the code with that in the database. A match in the code activates the transceiver, which starts to send radio frequency signals that can be detected by police cars and aviation units. Radio frequency can still be detected even when the car is hidden from plain sight.

While a GPS tracking unit is a really good option for car security system because you can access your car and its security options in real time, its use is not yet maximized by law enforcement agencies. Most state police still rely on radio transceivers to locate stolen vehicles.

Tracking systems are just additional security systems – very helpful if your car gets stolen or carjacked. Of course, it’s always better if your car does not get stolen. So there is still a need to install the standard security systems. First, there’s the car alarm. It may not be able to stop the thief from carjacking your vehicle but it does attract a lot of attention to the thief’s actions. Car alarms come in two forms, according to the activation method: active and passive. Active alarms are armed or disarmed once the user presses the transmitter button. Passive alarms automatically arm the vehicle once the engine is turned off and all the doors closed.

Car alarms have been enhanced over the years. Passive alarms, for example, have been taken to another level by the forced passive arming. Unlike the ordinary passive alarm wherein all the doors should be closed before the vehicle is armed, forced passive alarm will arm the vehicle after some time even if a door (or doors) has been left open. Being in the age where wires are slowly being removed, there are now wireless GSM car alarms. These devices are easily concealed because they are not attached to any wires. It also makes use of the GSM technology, such as when the general power is clipped, it will alert the car owner through his mobile phone.

Car alarms can be triggered by sensors which now come in many types. Motion sensors trigger the alarm when it detects movements made on the car even when the car doors and windows are open. Some motion sensors now make use of radar to detect movement both inside and outside the vehicle. Glass-tampering sensors detect the frequency generated by breaking glass which is valuable in cases wherein the thief tries to get into your car by bypassing the door. A car security system can have more than one sensor to trigger the alarm.

Sensors and car alarms can come with keyless entry systems and remote auto security which allows you to lock and unlock car doors, turn on the headlights and start your car's engine without the use of keys. You only have to use your keychain remote control to access the anti-theft capabilities of your car.

A car security system, however, does not give one a reason to be complacent. It always pays to be vigilant, such as making sure that the car is parked in well-lit places where the thief is likely to be seen should he decide to break in. Although an auto security system is a must especially in urban places, its always a relief if they never have to work.