What is PKES and what are its risks?

What will be an ideal response?

Many cars today offer a Passive Keyless Entry and Start (PKES) system, which allows the driver to unlock the doors and start the car without having to take the key out of her pocket or purse. All a driver has to do is get close enough to the car for the wireless signal from their key fob to be detected by the car, and once detected the doors automatically unlock and the engine can be started by pushing a button on the dashboard. One risk of a PKES is that an attacker can use an amplifier to strengthen the signal from the key fob to the car, thereby giving the attacker access to the car even though the key fob may be up to 50 feet away.