The term tip and ring originated in the cordboard plugs that establish the connection between the copper wire pairs. The tip of the plug connects to the electrically positive (+) wire, and the ring, or seat of the plug, to the electrically negative (
The divisions of the plug in phone, mini-phone and sub-mini connectors that represent the different conductors. Tip (T) and ring (R), along with the sleeve (S), are used in two-conductor (TS), three-conductor (TRS) and four-conductor (TRRS) variations. This terminology originated from the early days of telephones when operators manually plugged lines into a manual switchboard. Today, there are myriad audio applications that use two conductors (TS) for mono and three conductors (TRS) for stereo. See phone connector and mini-phone connector.