What is Parallel?
What is Parallel Port?
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A parallel interface for connecting an external device such as a printer. Most personal computers have both a parallel port and at least one serial port.
On PCs, the parallel port uses a 25-pin connector (type DB-25) and is used to connect printers, computers and other devices that need relatively high bandwidth. It is often called a Centronics interface after the company that designed the original standard for parallel communication between a computer and printer. (The modern parallel interface is based on a design by Epson.)
A newer type of parallel port, which supports the same connectors as the Centronics interface, is the EPP (Enhanced Parallel Port) or ECP (Extended Capabilities Port). Both of these parallel ports support bi-directional communication and transfer rates ten times as fast as the Centronics port.
Macintoshes have a SCSI port, which is parallel, but more flexible
A standard interface for connecting printers and other parallel devices. Although Centronics Corporation designed the original standard, the Centronics interface used by modern computers was designed by Epson Corporation. For PCs, almost all parallel ports conform to the Centronics standard. Two new parallel port standards that are backward compatible with Centronics, but offer faster transmission rates, are ECP (Extend Capabilities Port) and EPP (Enhanced Parallel Port).
ECP
Short for Extended Capabilities Port, a parallel-port standard for PCs that supports bi-directional communication between the PC and attached devices (such as a printer). ECP is about 10 times faster than the older Centronics standard.
EPP
Short for Enhanced Parallel Port, a parallel port standard for PCs that supports bi-directional communication between the PC and attached non-printer devices. EPP is about 10 times faster than the older Centronics standard.