Overview of SATA
Parallel ATA (PATA) is the widely used standard for interfacing between computers and hard drives. In 2002, Serial ATA (SATA) was introduced as the next step in ATA technology. SATA provides greater scalability, simpler installation, thinner cabling, and faster performance (up to 3 Gb/s). SATA maintains backward compatibility with parallel ATA drivers. Users of the SATA interface benefit from greater speed, simpler upgradeable storage devices and easier configuration. SATA, which represents the evolution of the ATA interface from a parallel bus to a serial bus architecture, overcomes the electrical constraints that inhibit continued speed enhancements for the classic parallel ATA bus.

SATA Specifications
The SATA technical specifications (SATA II and SATA 1.0a) are available for download from the SATA-IO Website.