parallel port (redirected from Paralell communications)

(1) A hardware interface that transfers one or more bytes simultaneously. See parallel interface.

(2) A socket on a computer used to connect a printer or other device via a parallel interface. In the past, the parallel port was widely used for printers. Although slower than internal interfaces, it was also used as an alternate way of cabling two computers together for data transfer and connecting external drives and other peripheral devices. On PCs, the port first appeared on plug-in cards, but was later built into the motherboard.

It Goes Back to the 1970s
The Centronics Data Computer Corporation, a subsidiary of Wang Laboratories in the 1970s, introduced a parallel port for printers. It was adapted for the IBM PC in 1981 and enhanced and standardized by the IEEE in 1994. Although some business printers still come with a parallel port, the interface typically is no longer included as standard equipment on PCs. See Centronics interface and IEEE 1284.

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(hardware)

parallel port - An interface from a computer system where data is transferred in or out in parallel, that is, on more than one wire. A parallel port carries one bit on each wire thus multiplying the transfer rate obtainable over a single wire. There will usually be some control signals on the port as well to say when data is ready to be sent or received. The commonest kind of parallel port is a printer port, e.g. a Centronics port which transfers eight bits at a time. Disks are also connected via special parallel ports, e.g. SCSI or IDE.