plugboard

thumb|IBM 402 accounting machine control panel wiring. This board was labeled "profit & loss summary." thumb|Reverse side of the same 402 plugboard, showing the pins that make contact with the machine's internal wiring. The holes were called hubs. A plugboard or control panel (the term used depends on the application area) is an array of jacks or sockets (often called hubs) into which patch cords can be inserted to complete an electrical circuit. Control panels are sometimes used to direct the operation of unit record equipment, cipher machines, and early computers. The array of holes is often