Transceiver is a device that has transmitter and receiver in a single package. It is a device that both transmits and receives analog or digital signals. The term is used most frequently to describe the component in local-area networks (LANs) that actually applies signals onto the network wire and detects signals passing through the wire. In ethernet networks, a transceiver is also called a Medium Access Unit (MAU). In radio communications, a transceiver is a two-way radio that combines both a radio transmitter and a receiver that exchanges information in half-duplex mode. Some transceivers are designed to allow reception of signals during transmission periods. This mode is known as full duplex, and requires that the transmitter and receiver operate on substantially different frequencies so the transmitted signal does not interfere with reception.