Digital degradation
I am always telling people that they need to backup their digital stuff. Documents, pictures, config files – you have to make copies of all of it. LOCKSS – “Lots Of Copies Keeps Stuff Safe” as Google says.
In recent years, I’ve become a fan of backup software such as Norton Ghost, or more recently StorageCraft’s ShadowProtect (Norton licenses the heavy lifting guts of Ghost from them). While this software will make a backup image of your entire hard drive, operating system and all (which makes for a super easy disk replacement), the confidence you get from that backup might lead you to forget about the other important backup: archiving.
If you get an external hard drive and set up your backup software to use it, chances are you only keep a few weeks or months of rotating backups. ShadowProtect and the like will automatically delete older backups to make room for new ones, so you don’t have to worry about freeing up disk space. But every now and then, you should still take your most important data and make a backup archive of it to DVD or some other media.
Now why would you have to do that? After all, that rotating backup contains the same stuff, doesn’t it? Well, the answer is yes, but what happens if a file gets corrupted or damaged in some way? Maybe your backup software or some other checking from the operating system will catch such a thing, but maybe it won’t.
Case in point – here is a picture from a 2003 trip that randomly came up in the sidebar on my desktop:
Clearly, something has happened to this digital photo. The backup software has been happily keeping a rotating copy of this picture all along, having purged the undamaged original at some point.
Now, here is the same picture as stored on a DVD archive made in 2004:
The prosecution rests. Go buy some blank DVDs and get to burning, Jack!