eSATA (External Serial ATA) is an interface standard used to connect external storage devices like hard drives and SSDs to a computer. It offers faster data transfer speeds than USB and FireWire, typically reaching up to 6 Gbps with eSATA III. eSATA provides a direct connection to the computer’s internal SATA controller, ensuring reliability and high performance, making it ideal for data-intensive applications. However, it requires a separate power source for devices.