A key fob is a small electronic device used to control access to a vehicle or building. It typically contains buttons that allow users to lock or unlock doors, start the engine, or activate an alarm system. Key fobs communicate wirelessly with a receiver in the vehicle or security system, making it convenient for users to operate their locks without using a traditional key. Many modern vehicles, such as those from Ford or Toyota, come with key fobs as standard equipment. Some key fobs also include additional features, like remote start or panic buttons, enhancing security and convenience for users.