Your hard-disk has millions of photographs, music of every genre, college papers, and mountains of e-mail messages.
Yet no one has figured out how to preserve these electronic materials for the next decade, much less for the ages. Like junk e-mail, the problem of digital archiving, which seems straightforward, confounds even the experts.
In the meantime, individual PC owners struggle in private. Desk drawers and den closets are filled with obsolete computers, stacks of Zip disks and 3½-inch diskettes, even the larger 5¼-inch floppy disks from the 1980's. Short of a clear solution, experts recommend that people copy their materials, which were once on vinyl, film and paper, to CD's and other backup formats.
But backup mechanisms can also lose their integrity. Magnetic tape, CD's and hard drives are far from robust. The life span of data on a CD recorded with a CD burner, for instance, could be as little as five years if it is exposed to extremes in humidity or tempe