USB It has largely replaced interfaces such as serial ports and parallel ports, and has become commonplace on a wide range of devices. USB connectors have been increasingly replacing other types for battery chargers of portable devices. This section is intended to allow fast identification of USB receptacles (sockets) on equipment. Further diagrams and discussion of plugs and receptacles can be found in USB (Physical) § Connectors. The Universal Serial Bus was developed to simplify and improve the interface between personal computers and peripheral devices, when compared with previously existing standard or ad-hoc proprietary interfaces. From the computer user's perspective, the
Serial port a 9-pin D-subminiature connector is not sufficient to indicate the connection is in fact a serial port, since this connector is also used for video, joysticks, and other purposes. Some miniaturized electronics, particularly graphing calculators and hand-held amateur and two-way radio equipment, have serial ports using a phone connector, usually the smaller 2.5 or 3.5 mm connectors and use the most basic 3-wire interface. Many models of Macintosh favor the related RS-422 standard, mostly using German mini-DIN connectors, except in the earliest models. The Macintosh included a standard set of two ports for connection to a printer and a modem,