A repeater is a device used in telecommunications to receive and amplify signals, allowing them to travel longer distances without losing quality. It works by taking an incoming signal, boosting its strength, and then retransmitting it. This is especially useful in areas where signals may weaken due to distance or obstacles. Repeaters are commonly used in various applications, including cellular networks, Wi-Fi networks, and broadcasting. They help improve coverage and connectivity, ensuring that users can maintain a strong signal even in remote or obstructed locations.