External USB hard drives are available in a variety of shapes and sizes, from larger models that often require a mains power source, to lighter, more portable drives that take their power from the USB port instead.
Hard drives are a popular means for backing up data. They're good value, simple to use, and small enough to carry around with ease.
But they're not without their problems, and it's worth considering the cons of an external hard drive before trusting all of your data to them.
Why should you back up to a hard drive?
What are the pros and cons of using a hard drive to back up your data?
Pros of hard drive backup
Backing up to a hard disk drive is cheap. Costs vary depending on the capacity of the drive, and the bigger you go, the cheaper it works out per gigabyte.
You can buy a 500GB USB drive for around £40 online. A high-capacity 2TB hard drive typically works out at around 4p per GB.
Another benefit of using a hard drive is how quickly they can back up files. Copying data to a hard drive is far faster than uploading to online storage or burning to DVD or CD.
Newer hard drives have USB 3.0 connections that make data transfer even speedier, though you will need a corresponding USB 3.0 port on your PC to get the benefit.
Another useful type of hard drive is a NAS (network attached storage) drive. This is a special type of hard disk with a wired or wireless network connection. A drive like this lets multiple PCs back up and access files, and you can place it anywhere in your home, provided it can connect to your home network.
Cons of hard drive backup
The biggest problem with making backup copies to any type of hard drive is that they aren’t immune to the same problems that afflict PCs. Loss, theft, damage, data corruption or mechanical failure are all risks.
With all of your files backed up on one drive, they’re still vulnerable. As such, this method is not 100% foolproof.
How to back up to a hard drive
The manual method of backing up to a hard drive
A crude way to back up data is simply to drag and drop important files from your PC’s hard drive onto an external one. However, this approach makes it easy to miss a vital folder, to drag from the wrong drive, or simply forget to do it.
It’s therefore best to use a program that has been designed to automate the process, carrying out regular scheduled backups. Thankfully, many external hard drives come with their own backup software.
Using Windows backup
Windows itself has a simple yet perfectly serviceable built-in backup utility.
To use this, press the Windows key on your keyboard, and type backup.
In Windows 7, click the Backup & Restore link that appears. There are essentially two main types of backup option. The first is file-and-folder backup, where you choose specific files and folders that are to be copied. The second, disk image backup, makes a copy of everything on your PC’s drive, including all files, programs and even Windows itself.
The cheap cost of large-capacity external hard drives often makes it possible to do both, and we recommend doing so if you can. Windows’ built-in backup utility allows for both approaches.