Just like conventional negatives, your original digital image files are irreplaceable and should be looked after carefully. Storing them on a computer hard disc without having a back up is unsafe, since a computer crash will effectively erase or damage all your images.
Opinions vary on the best way to preserve original image files. Some say burning them on quality CD-R/DVDs and storing them in a cool dark place, should make them last for up to 100 years, while others claim their maximum life span is no more than 2 -5 years. You should not use rewritables as their life span is much shorter due to the dye used in the manufacturing process.
Save images in uncompressed form since JPEG-compression will degrade an image every time you save it. When burning CDs or DVDs, arrange images in folders according to date or subject matter and include a contact sheet to make locating them easier. Make two copies of each CD/DVD and store them in different places.
Home made prints should be stored in binders or boxes since they can be prone to fading if exposed to direct (sun)light. For framed prints protective UV sprays are available and most manufacturers now use archival inks that should last for many years. Keep prints away from coffee or other drinks as stains will not wash out.