Intercoms are communication systems used to transmit audio or video signals within a building or network of buildings. There are various synonyms for intercoms like audio systems, communication devices, microphones, transceivers, walkie-talkies, and two-way radios. An audio system refers to an electronic system that processes sound waves. Communication devices are tools used to transfer information between people or groups. Microphones are devices that amplify sound waves and convert them into electrical signals. Transceivers are devices that both transmit and receive signals. Walkie-talkies are handheld devices that are used for communication over short distances. Two-way radios are wireless communication devices that allow communication between people and systems.