Various types of SATA standards are as follows :
SATA150
First-generation Serial ATA interfaces, also reffered to as SATA150. It uses 8B/10B encoding at the physical layer resulting in an actual data transfer rate of 150 Mbps.
SATA300
With the release of the Nvidia nForce4 chipset in 2004, the maximum throughput has been doubled (increased) to 300 MB(s), which is very widely referred to as “Serial ATA II”.
External SATA
In the beginning, SATA was designed as an internal or inside-the-box interface technology to bring out improved performance and added features to internal PC or consumer storage. Its success led the designers to design SATA outside the box too extending its features. External SATA or eSATA as it is commonly referred to, has a high performance when compared with USB or IEEE 1394 Interfaces. The shielded cables run upto 2 meters outside the box allowing it to connect or take advantge of SATA externally.
Benefits of ESATA
Up to 6 times faster than existing external storage solutions such as USB 2.0 & IEEE1394.
Robust and user friendly external connection.
High performance, cost effective expansion storage.
Up to 2 meter shielded cables and connectors.
