Winn L. Rosch Hardware Bible, Sixth Edition

SCSI Parallel Interface

Pronounced scuzzy by much of the computer industry (and much less often sexy by its most fervent advocates), SCSI is a system-level interface that provides what is essentially a complete expansion bus into which to plug peripherals. SCSI isn't simply a connection that links a device or two to your computer. Rather, it functions like a sub-bus. SCSI devices can exchange data between themselves without the intervention of the host computer's microprocessor. In fact, they can act across the SCSI bus even while other transfers are shifting across the host computer's normal expansion bus.

SCSI is even older than ATA. In fact, it's effectively the oldest interface still in use in personal computers. Originally simply a means ...