An eSATA connection enables external hard drives to connect with the same 6.0 gigabits per second (Gbps) or 3.0 Gbps speeds as internal SATA 6 and 3 connections. This enables external drives to work just as effectively as internal drives for accessing data and, in some cases, booting your computer. Not all BIOS supports booting from eSATA devices, but for those that do, you have the option of quickly changing boot drives to run varying operating systems or boot utilities without ever cracking open your computer. Writer Bio
