serial port

port used for a serial connection between communication devices, interface for serial communication between peripheral devices (Computers)

In computing, a serial port is a serial communication physical interface through which information transfers in or out one bit at a time (contrast parallel port). Throughout most of the history of personal computers, data transfer through serial ports connected the computer to devices such as terminals or modems. Mice, keyboards, and other peripheral devices also connected in this way.
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Noun
1. an interface (commonly used for modems and mice and some printers) that transmits data a bit at a time
(hypernym) interface, port

A port through which data are passed serially, i.e. , one bit at a time, and that requires only one input channel to handle a set of bits, e.g., all the bits of a byte. Contrast with parallel port.

<hardware, communications> (Or "com port") A connector on a computer to which you can attach a serial line connected to peripherals which communicate using a serial (bit-stream) protocol. The most common type of serial port is a 25-pin D-type connector carrying EIA-232 signals. Smaller connectors (e.g. 9-pin D-type) carrying a subset of EIA-232 are often used on personal computers. The serial port is usually connected to an integrated circuit called a UART which handles the conversion between serial and parallel data.
In the days before bit-mapped displays, and today on multi-user systems, the serial port was used to connect one or more terminals (teletypewriters or VDUs), printers, modems and other serial peripherals. Two computers connected together via their serial ports, possibly via modems, can communicate using a protocol such as UUCP or CU or SLIP.
(1995-01-12)