USB 2.0
If you have a choice, select it instead of: USB 1.0
It's similar in performance and use to: FireWire 400, eSATA
It adapts to: Other USB shapes
Add more ports by: Installing a PCI-card upgrade; connecting a hub
Significantly faster than the original USB, the 2.0 version usually connects with an "A" end on a PC and a Mini-USB end on a peripheral. Some of the tiniest gadgets on the market opt to use the Micro-USB end. The faster bus of USB 2.0 means that it's much more suited to hard disks and to network adapters than the original version is.
SATA
If you have a choice, select it instead of: ATA
It's similar in performance and use to: eSATA
It adapts to: eSATA
Add more ports by: Inserting an additional PCI controller card
Serial ATA connects internal disks within PCs. Many new computer case designs allow you to slide in a hard drive so that it meets directly with a port; otherwise, you'll use a cable. The fastest, most widely implemented version (often misnamed SATA II) runs at 3 gigabits per second and provides enough speed for the most disk-demanding tasks, such as high-end video capture.
eSATA
Use it for: External hard drives, Blu-ray and DVD-burners, and other disks; DVRs often support an eSATA drive for more storage space
If you have a choice, select it instead of: USB 1.0, FireWire 400
It's similar in performance and use to: USB 2.0, FireWire 800
It adapts to: SATA
Add more ports by: Inserting an additional PCI controller card
eSATA, a variant of SATA, simply takes that technology outside of a PC. eSATA is shielded from electrical interference and offers other considerations for making the move outside the case, and as a result is compatible with any kind of external disk.