Headers, Receptacles, Female SocketsHeaders, receptacles, and female sockets are all types of rectangular electrical connectors. Headers are a type of connector that consists of a row of metal pins or sockets. They are typically used to connect two circuits or to connect a circuit to a device, such as a sensor or an actuator. Receptacles are the corresponding connectors that mate with headers. They are typically used on printed circuit boards (PCBs) or other devices and have a row of holes into which the pins on a header can be inserted. Female sockets are similar to receptacles, but they have a row of metal sockets rather than holes. They are typically used to connect a cable or other external device to a circuit or PCB.