Plugs (P) and jacks (J) can have either pin contacts, socket contacts, or a combination of pin and socket contacts. Gender nomenclature applies more to pin (male) and socket (female) contacts, where plugs are simply the most movable, and jacks the least movable of a connector pair. Connector reference designations simply assign a number to either P or J, such as P5 and J3. Designation of individual contacts of a connector can be numbers, uppercase single or double letters, lowercase single or double letters, and even symbols, and are associated by a dash (-) to the reference designation of their connector, such as P5-12 and J3-aa. Electrical source contacts are usually sockets which are safely recessed into the connector face. Observing these principles have never failed me and have minimized confusion in describing connections.
