The purpose of a wireless doorbell is to provide a convenient way to signal a person's arrival at a door without the need for complex wiring. Key features and description: Functionality: The remote button, when pressed, sends a radio frequency (RF) signal to the main chime unit, which then plays a sound or "ding dong" tune. Installation: It is designed for easy installation, often using double-sided adhesive tape, and does not require any wiring. Power: The units are typically battery-powered, with the remote button often using a smaller battery and the main chime unit using AA batteries or plugging into a wall outlet. Use: Wireless doorbells are suitable for homes, offices, factories, and other locations.