A telephone switchboard is a telecommunications system used in the public switched telephone network or in enterprises to interconnect circuits of telephones to establish telephone calls between the subscribers or users, or between other exchanges. 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.
Following the invention of the telephone in 1876, the first telephones were rented in pairs which were limited to conversation between the parties operating those two instruments. The use of a central exchange was soon found to be even more advantageous than in telegraphy. In January 1878 the Boston Telephone Dispatch company had started hiring boys as telephone operators. Boys had been very successful as telegraphy operators, but their attitude, lack of patience, and behavior was unacceptable for live telephone contact, so the company began hiring women operators instead.
On September 1, 1878, Boston Telephone Dispatch hired Emma Nutt as the first woman operator. Small towns typically had the switchboard installed in the operator's home so that he or she could answer calls on a 24 hour basis.
In 1894, New England Telephone and Telegraph Company installed the first battery-operated switchboard on January 9 in Lexington, Massachusetts.
Which building has the largest telephone switchboard in the world? "The Pentagon building was a focus of statistical bewilderment: population capacity 40,000; a telephone switchboard big enough for a city of 125,000; enough pavement for a 24-ft. roadway 49 miles long, including parking space for 8,000 cars."