Best external drives(Updated December 10, 2013 1:55 AM PST)
An external hard drive has three main purposes: to expand your computer's storage capacity, to back up your data, and to share data between computers. It's also easy to use. Most of the time, you just need to plug it into the computer and use it as an internal hard drive. Desktop external hard drives are based on the 3.5-inch internal hard drives, and laptop (or portable) external hard drives are based on the 2.5-inch internal hard drives.
Here's a current list of the top external drives.