The SCSI command set provides efficient peer-to-peer operation of input/output devices (disks, tapes, printers, etc.) by an operating system.

This International Standard defines the SCSI commands and model for indepedent medium changer devices and attached medium changer functions integrated into other SCSI devices. This includes the commands and external behavioural characteristics of a device server, and the behaviour of the attached medium changer commands (SMC).