"Digital files offer some advantages and some disadvantages over film in terms of storage. The important thing is to plan for it, and then make sure you put those plans into practice. The key files to store are the raw files direct from camera - the digital equivalent of your negatives. It may also be convenient to store the processed tiff or jpeg files, but these could always be recreated from the originals."
If you own a digital camera and/or have a large collection of digital images you definitely need to get this article on About.com a read.
About.com: Filing and Finding your Images
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