Terminal (electronics)

For other uses, see Terminal (disambiguation).

"Pole (electrical circuits)" redirects here. For the poles of switches, see Switch § Contact terminology.

A terminal is the point at which a conductor from a component, device or network comes to an end.^[1] Terminal may also refer to an electrical connector at this endpoint, acting as the reusable interface to a conductor and creating a point where external circuits can be connected.^[2][3] A terminal may simply be the end of a wire or it may be fitted with a connector or fastener.^{[citation needed]}

In network analysis, terminal means a point at which connections can be made to a network in theory and does not necessarily refer to any physical object. In this context, especially in older documents, it is sometimes called a pole. On circuit diagrams, terminals for external connections are denoted by empty circles.^[4] They are distinguished from nodes or junctions which are entirely internal to the circuit and are denoted by solid circles.^[5]

All electrochemical cells have two terminals (electrodes) which are referred to as the anode and cathode or positive (+) and negative (–). On many dry batteries, the positive terminal (cathode) is a protruding metal cap, and the negative terminal (anode) is a flat metal disc (see Battery terminal). In a galvanic cell such as a common AA battery, electrons flow from the negative terminal to the positive terminal, while the conventional current is opposite to this.^[6]