SAS may refer to any of the following:
1. Short for Serial Attached SCSI, SAS is a serial transmission replacement for the parallel SCSI. SAS is an improvement of traditional SCSI in that it supports a maximum of 128 simultaneous devices, at transmission speeds of 3.0 Gb/s. SAS devices have two data ports, and can communicate with both SCSI and SATA.
2. Short for Standalone Server, SAS is a server that does not rely on any other servers or services.