eSATA is an external interface technology that grew from the internal Serial ATA interface. Serial ATA built upon the original ATA interface that connected hard drives to motherboards. eSATA delivers improved performance and ease of use over the older ATA multi-pin interface.
eSATA, or external SATA, allowed for the use of shielded cables outside of an enclosure. Shielded eSATA cables are available up to 2 meters in length. eSATA cables are not the same as SATA I cables, they are shielded and have a different connector than the L shaped design of internal SATA I connectors. This prevents the use of unshielded internal cables in external applications. eSATA uses a point-to-point connection, therefore each eSATA drive needs to be connected to its own eSATA port.
The eSATA port on the GT 050Q supports speeds up to 1.5 Gb/sec (150 MB/sec), much faster than FireWire 400 or FireWire 800. The eSATA port on the GT 062E and ForteRAID support speeds up to 3 Gb/sec (300 MB/sec). If your computer does not have built-in eSATA, you'll need a PCI card to connect your drive with eSATA. Glyph sells PCI cards with 2 or more ports to accommodate your drives.