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Backup Plan: Tools for Cloud Storage and Backup: External Hard Drives

This guide accompanies the Backup Plan WICshop.

What is an External Hard Drive?

An external hard drive is a device for storing data that exists outside your computer's built in hard drive. It usually plugs into your computer using a cable, like USB or FireWire. It generally has higher storage capacity than your built in hard drive, sometimes significantly higher.  Some external hard drives need to be plugged in, but many are portable and work off of your computer's electricity.  There are even wireless drives and drives that work as personal cloud storage.

Which Hard Drive Should I Buy?

You may have to shop around for a hard drive that meets your requirements for capacity, quality, and price. Here are some links to reviews of hard drives to help you get started.

Why Buy an External Hard Drive?

Storing files on an external hard drive is a very simple way to save copies of important documents. You can organize files into folders the same way you would on your built in hard drive. You can also set up automatic backups of certain folders or your entire hard drive on your external drive (more on this under the Data Backup Services tab above).

External hard drives are also increasingly cheap ways to backup files. You can generally purchase a terabyte of storage for under $100. To give you a sense of how much space that is:

visualization of a terabyte of data

Considerations and Advice

Here are some considerations that you should think about when choosing an external hard drive:

  • Capacity:  The storage capacity of external drives ranges from 60 GB to 4TB, and up.  Get the drive with the largest capacity you can afford; it will save you from having to buy another drive later.
  • Speed:  Solid state drives (SSDs) tend to be faster and less susceptible to impact damage than hard disk drives (HDDs), but are also more expensive.  For HDDs, higher rotation speeds will provide better and faster performance (7,200 rpm vs. 5,400 rpm).
  • Connectivity:  The current trend is towards faster connections, such as Thunderbolt, but most drives will also have USB 3.0 (backward compatible with USB 2.0).  Make sure to check that your computer is compatible with the drive.
  • Security:  Most drives will come with (optional) password protection, but some newer drives include more sophisticated encryption or biometric security, although this will add to the cost.
  • Portability:  If you are going to be moving the drive around, you should get a portable drive that will work off of your computer’s electricity.  Some drives are “shock proof” and will resist damage when dropped.  Carrying cases are also available.
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