Optical media also degrade quickly unless you use high-quality, low-density media. Most of my CD-Rs from 10 years ago still work fine, but many DVD-Rs get corru

Optical media also degrade quickly unless you use high-quality, low-density media. Most of my CD-Rs from 10 years ago still work fine, but many DVD-Rs get corrupted after only 2-3 years. Seriously, I've had better luck with spinning rust than I've had with optical discs. The only way to make sure that a backup lasts more than a couple of years is to copy it to new media every couple of years.