What is Serial ATA?
Serial ATA is an enhancement to the ATA standard for for connecting data storage devices to computers.
All versions of ATA up to ATA-7 utilized parallel transfer of data from the motherboard to the drive controller built onto the disk.
The ATA-7 specification introduced Serial ATA in 2004..
Serial ATA Standards
The original Serial ATA standard offered miniminal performance improvement over the existing 133MBps bandwidth of the Parallel ATA standard.
Serial ATA standards are constantly evolving to meet higher bandwidth requirements:
Serial ATA Data Cables
Higher bandwidth requirements were forcing requirements for shorter Parallel ATA data cables. Serial ATA resolved this issue by enabling data cables up to 1 meter in length.
eSATA (External SATA) allows the use of shielded cables up to 2 meters in length for external drives.
Serial ATA Power Cables
Serial ATA power cables use a 15-pin wafer connector to provide 3.3v, 5v, or 12v power to ATA devices.