The precise difference between a plug and socket varies, depending on the specific industry and country of origin. Generally, plugs have prongs that fit into slots in a socket. Pins, prongs, or other protrusions on a plug are called male ends. Slots, holes and other receptacles on a socket are called female ends. Typically, sockets are fixed in place, such as in a wall or other permanent fixture. Alternatively, a plug is movable, attached to an appliance, electronic device or other portable mechanism.
In computer electronics, the difference between a plug and socket can be slightly different than electrical outlets or receptacles. For example, a monitor plug is comprised of numerous pins that fit into a socket or port on the back of a computer processing unit (CPU.) Likewise, CAT5 cables, used to connect computers to routers and modems, have a plastic plug comprised of several wires housed inside a plastic clip. CAT5 plugs fit into a recessed socket at the back of the router or modem and snap into place via the plastic clip.
Aside from the differences of placement and general physical appearance, specific applications can result in a variety of differences between a plug and socket. Some applications, in an effort to protect people and equipment from electrical hazards, necessitate specific physical differences. Grounding, for example, may require a plug to have three or more prongs in a set pattern. Only sockets with slots or holes situated in an identical mirrored pattern can accept such plugs.
Various plug and socket configurations, and their appropriate appearances and differences, vary from country to country. They can differ in nomenclature, physical characteristics, and required features. Terms such as plug and socket, or power cord and outlet, have different meanings and characteristics depending on American or European standards. Regardless of industry or country of origin, understanding the differences between the two merely requires understanding that each component is symbiotic with the other. Plugs fit into sockets to connect two parts, typically to complete an electrical circuit or create a network of interconnected devices. Each component is fashioned to accept connection to its matching counterpart.
With this concept in mind, a plug and socket can be seen as two removable parts of a whole. A socket can be thought of as a negative image of its matching plug, with recesses in the socket to accommodate protrusions in the plug. How each component compares or illustrates differences depends on whether the components are for electrical devices, computer equipment, manufacturing facilities, or another application.