Serial Attached SCSI (
SAS) is a point-to-point serial protocol that moves data to and from computer storage devices such as
hard drives and
tape drives. SAS replaces the older
Parallel SCSI (
Small
Computer
System
Interface, pronounced "scuzzy") bus technology that first appeared in the mid-1980s. SAS, like its predecessor, uses the standard
SCSI command set. SAS offers backward compatibility with
SATA, versions 2 and later. This allows for SATA drives to be connected to SAS
backplanes. The reverse, connecting SAS drives to SATA backplanes, is not possible.