eSATA is an acronym for External Serial Advanced Technology Attachment. SATA technology was originally used to transfer data to and from an internal hard drive or CD-ROM. eSATA was developed based on SATA, but geared toward connection of external devices as an alternative to USB and IEEE 1394 (FireWire). eSATA is emerging as an external standard and can be faster than USB 2.0 or FireWire since USB and FireWire devices utilize a bridge chip to convert the data to ATA while eSATA needs no conversion. eSATA is hot swappable.