Today, this system is commonly found on a variety of vehicles, and although the exact method of operation differs between makes and models, their operation is generally similar: a vehicle can be unlocked without the driver needing to physically push a button on the key fob to lock or unlock the car and is also able to start or stop the ignition without physically having to insert the key and turning the ignition. Instead, the vehicle senses that the key (which may be located in the user's pocket, purse, etc.) is approaching the vehicle.