Over the years, cars have certainly changed a lot and so have the car keys that ignite them. Modern car keys have a chip embedded in the plastic. The chip is a part of the transponder that checks if the correct key is used in the lock. The car transmits a signal the moment the key is inserted into the lock. Then, the chip inside the key receives the signal and makes calculations and responds to the signal sent by the car. The key then confirms that the correct match is inserted into the lock and the car is ready to start.