Beginners Guide To External Hard Drives
External hard drives offer two main advantages over their internal cousin. They make it easy for the non-technically inclined to add data storage capacity to their PCs without cracking open the case, and they are great when you want to take a whole bunch of your data with you to a remote computer. Most computer users have no real need for external hard drives, but those who do usually swear by them.
Here are the basics so any computer user can master the lingo:
Form Factor: There are small external boxes for tiny 2.5 inch hard drives designed for laptops which are intended for maximum portability, and huge cases which can hold five or more full size hard drives and can hold several terabytes of data. Most external hard drive units on the market just hold one full size 3.5 inch drive and they are the most popular and affordable kind.
Capacity: Just like internal hard drives, you should be very careful to estimate your expected data amounts and at least double that figure. The bigger hard drive the better! You may find that you can save a lot of money by buying an external hard drive very cheaply that only holds 80 GB or so and with just one phillips screwdriver, replace that internal mechanism with a new 500 GB or even 1 TB drive. The final price will likely be less than just buying a large capacity hard drive, and you'll have an extra new small drive that you can use in a Home Theatre or hand-me-down computer. You might as well buy an 80 GB external rather than an empty external case as they cost about the same!
Connection Interface: Most modern external hard drives utilize USB 2.0 or FireWire 400 to connect to the main PC. Some of the newer and more expensive models will use FireWire 800 (twice as fast as the 400) or External SATA (eSATA) which is even faster than FireWire 800. The drawback with eSATA is that they generally require you to install a PCI card in the desktop PC or a type of ExpressCard in a laptop. Some external hard drives will even have two or more of these connection interfaces. Generally speaking USB 2.0 and FireWire 400 transfers will be more than fast enough for any mere mortal.
Power Source: Unless you are a rabid mobility addict, avoid the bus-powered drives that get their power from the USB or FireWire port. These types of drives are very handy to use with laptops out in the field, but have a tendency of sucking your battery dry at an amazing rate. In some cases a fully-charged laptop with an external hard drive can go flat in half an hour. The AC powered external hard drives should suffice for most applications.
Software: Some external hard drives come bundled with some superlative backup and recovery software packages which have a retail value that can be even higher than the hard drive unit itself! Do your homework and pick out the external hard drive that comes with the software you prefer.
Picking out the right external hard drive for your needs can be even more confusing than choosing an internal hard drive. You have all the aspects of the internal, plus the added elements of the external to deal with. Take your time, do your homework, and you'll get the best model for your requirements and budget!