A switchboard was a device used to connect a group of telephone

Telephone

The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...

s manually to one another or to an outside connection, within and between telephone exchange

Telephone exchange

In the field of telecommunications, a telephone exchange or telephone switch is a system of electronic components that connects telephone calls...

s or private branch exchanges (PBXs). The user was typically known as an operator

Telephone operator

A telephone operator is either* a person who provides assistance to a telephone caller, usually in the placing of operator assisted telephone calls such as calls from a pay phone, collect calls , calls which are billed to a credit card, station-to-station and person-to-person calls, and certain...

. Public manual exchanges disappeared during the last half of the 20th century, leaving a few PBXs working in offices and hotel

Hotel

A hotel is an establishment that provides paid lodging on a short-term basis. The provision of basic accommodation, in times past, consisting only of a room with a bed, a cupboard, a small table and a washstand has largely been replaced by rooms with modern facilities, including en-suite bathrooms...

s as manual branch exchanges.

The electromechanical automatic telephone exchange, invented by Almon Strowger in 1888, gradually replaced manual switchboards in central telephone exchanges.