A telephone switchboard was a device used to connect circuits of telephones to establish telephone calls between users or other switchboards, throughout the 20th century. The switchboard was an essential component of a manual telephone exchange, and was operated by switchboard operators who used electrical cords or switches to establish the connections.
PBX switchboard, 1975
Telephone operator, c. 1900
A large Bell System international switchboard in 1943
U.S. Air Force operator works a switchboard in the underground command post at Strategic Air Command headquarters, Offutt Air Force Base, Nebraska in 1967.
A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals that are transmitted via cables and other communication channels to another telephone which reproduces the sound to the receiving user. The term is derived from Greek: τῆλε and φωνή, together meaning distant voice. A common short form of the term is phone, which came into use early in the telephone's history.
An old rotary dial telephone
AT&T push button telephone made by Western Electric, model 2500 DMG black, 1980
Alexander Graham Bell's Telephone Patent Drawing
Replica of the telettrofono, invented by Antonio Meucci and credited by several sources as the first telephone.