Traditionally, backup has been carried out locally and this is still an option that most people will want to consider. The main options are an external hard disk, optical discs such as DVD or Blu-ray, or a USB flash drive if you don't have many large files to back up.
Optical discs are likely to be the most cost-effective: 4.7GB DVD-R discs cost less than 50p when bought in bulk making them slightly cheaper per GB than a typical 500GB portable hard disk. However, they're not the most convenient. You can’t schedule a backup at night, for example, because you’ll have to be present to swap discs.
For archiving, but not for backup, you’ll also have to give consideration to data longevity because this varies from one type of media to another. A hard disk will probably be reliable for five years although the risk of accidental damage is greater, and for flash drives 10 years has been suggested, but reports vary.
Exactly how long data lasts on optical media depends on a number of factors such as whether the disk is writable or re-writable, the manufacturer, and the environment in which it’s stored. Under optimum conditions data should be readable for a century but there have been reports of discs being unreadable after just two years.
We somehow doubt that DVD and Blu-ray drives will be around to read such disks in 100 years, so it's important to periodically write your archives to the latest media to ensure the files can be accessed by current hardware.
You should also give some thought to storage of your backup or archive media so that it isn’t lost in the event of a fire, flood or theft. Consider using a fireproof safe or, better still, storing it well away from your PC, perhaps in a friend’s house locally.
You can create local backups or archives with no special software at all, simply using Windows Explorer to copy files and folders to your backup media. However, dedicated backup software makes the job a lot easier and provides additional features too.
What to look for in backup software
Windows 7 has a built-in backup utility: Windows Backup and Restore - you'll find it if you type 'backup' into the Start menu search box. It's perfectly capable, but if you decide to investigate third-party applications there are some features you should look out.
Good backup software should be able to schedule backups so that they take place automatically at regular intervals. This is useful if you use an external drive which you leave connected to your computer. If the disk isn't attached the backup will fail. Similarly, scheduled backups aren't helpful if you're using optical disks as you'll have to insert them manually.
On the subject of multiple discs, backup software will automatically split the files and folders so each disc's full capacity is used. Depending on the software, it may produce a single file which can only be read by the program itself, or it may be readable by Windows natively.
Another common feature is support for incremental backups. This way, only files that have changed since the last backup are copied to the media to reduce the time taken to copy data. Compression can also reduce the time taken as less data has to be written.
Some applications are able to back up 'locked' files, which are those that you're working on during the backup process. Yet another thing to look out for is the ability to back up files and settings outside of your Documents, Photos, Music and Video folders, such as contacts, email, web browser bookmarks and even savegame files. It's crucial to ensure you're backing up everything you need to get back to where you were in the event of a disk failure.
In fact, some backup software offers the ability to backup your entire hard disk (this is known as disk imaging). The advantage of this approach is that in the event of a disk crash, recovery won’t involve re-installing all your software and setting up all the Windows options and preferences.
Creating a disk image is great if you need to recover from a major incident such as complete hard disk failure. However, the convenience comes at a cost, namely that backing up will be more time consuming and you’ll need to use much higher capacity media - usually another hard disk of the same size.
Our recommendation - and you may disagree - is not to bother with disk imaging. After all, disk crashes are relatively rare occurrences and if the worst does happen, having to start again from a blank hard disk will give you the opportunity to install Windows afresh and leave behind the flotsam and jetsam that slows Windows down after a while. What's important is that you have all your files and settings backed up plus your application CDs and DVDs (and serial numbers) to hand.
Next page: online backup