A telephone switchboard is a device used to connect circuits of telephones to establish telephone calls between users or other switchboards. The switchboard is an essential component of a manual telephone exchange, and is operated by switchboard operators who use electrical cords or switches to establish the connections.
The switchboard saw the peak of its use in the 20th century before wider adoption of the electromechanical automatic telephone exchange. The automatic exchange, invented by Almon Strowger in 1888, has replaced most switchboards in central telephone exchanges around the world.
Nevertheless, many manual branch exchanges remained operational into the second half of the 20th century in many enterprises. Some establishments, such as the White House, still operate a switchboard.
Electronic devices and computer technology have given exchange operators more features. For example, a private branch exchange (PBX) in a business usually has an attendant console, or an auto-attendant function, which bypasses the operator.