In today’s fast-paced world, many of us have become extremely dependent on the data we store on our computers. We create projects and even write articles that will never make it to hardcopy form, and we take photos upon photos with digital cameras but don’t always get prints to go with them. And let’s face it: do any of us really back up our data as often as we should?

Given that reality, it’s worth examining how much we can actually depend on the various types of data storage media we take for granted. How long does a CD-R or flash drive really last? Not as long as you might think.

CD-Rs (and DVD-Rs): Commercial music and software CDs tend to last for decades on end, but consumer-level CD-R and CD-RW discs do not. They are supposed to be valid for a few decades, or at least over 1,000 reads. But in most scenarios, CDs or DVDs you buy to burn at home only last 10-20 years at best, which may not be a great idea for that digital family tree or photo album you plan to share with future generations. Furthermore, when not stored correctly — that is, protected from light, dust, extreme temperatures, and other natural hazards of sitting idly around the house — they may have a shelf life of only a year or two. CD burners write to CDs by burning through a layer of organic ink on the CD surface, which can erode over time. Aside from natural wear, you can even damage a CD by attempting to clean it. So, you can help ensure maximum shelf life by storing your discs in lightproof containers, and if absolutely necessary, clean them off with single stroke from the center to the outer edge (running over the disc in a circle may scratch the surface and render the information unreadable). Even with optimal conditions, you should still be prepared to make replacement copies every few years.

Floppy Disks: They’ve been crowded out of the home data storage market lately due to their comparatively minuscule storage capacity, but floppy disks last much longer than optical storage media like CD discs. If you’re looking to back up equally small files, a simple old-fashioned floppy disk may be a good choice — as long as you make sure you’ll still have the drive to read it in years to come.

Magnetic Tape: Available in cassette or cartridge form, the same magnetic tape used in video cameras can be used as a data backup medium if the appropriate hardware is installed. Mag tape is much more long-lived than home CD or DVD media. The newest and best kinds of magnetic tape can hold up to 800 GB of uncompressed data, which essentially brings you the durability of a floppy disk with a much larger volume of storage space. The same cautionary storage principles used with CDs and DVDs apply to magnetic-based storage media, including floppy disks: store them away from light, dust, and excessive heat, and don’t touch or attempt to clean the working parts unless it’s absolutely necessary.

Flash Memory (USB, CF, SD, etc.): Though available in tidy space-saving packages, USB key RAM is only designed to be written over a certain number of times. That would be easy to deal with if the drive warned you when its memory was shot — but the problem is, it doesn’t, and you could be stuck with inaccessible and thus useless data before you even know it. I think we can all agree that this is Not Good. For tips on how to get around this issue, see our upcoming article on Long-Term Archival Tips.

External Hard Disk Drives: The best method for archiving digital information is probably to store it on a secondary hard disk drive. Removable HDD media that connects through a USB 2.0 port is now a commodity and that makes this a convenient option. Many of them, such as the Western Digital “Passport” even take their power from the USB port, so there’s no power supply to hassle with. It’s still cost prohibitive to use this option for a full set of rotating backups, but this is a good option for a “first line of defense” backup.

Hardcopy Printouts: Considering the durability and reliability problems inherent in digital media, it might be best to hold onto a hardcopy of important documents. Regular old paper has several levels of longevity, depending on the type and quality of the paper, ink, and printer used. You can also protect your print media with archival-quality, acid-free papers and covers, for truly important data. Keeping all that paper around may be a pain, but as optical character recognition technology becomes faster, easier, and more accurate, old-fashioned paper may be an optimal solution to your storage woes. If you’re still unconvinced, there’s one more upside to keeping a few hardcopies as backup. Those handy little CD and DVD-ROMs may outlive their compatibility with the hardware to come. Even today, standard notebook computers don’t have floppy disk drives — and how many of us have a mountain of VHS tapes sitting at home even though we no longer have a VCR?

Personal Photo Printers: Since maintaining hardcopies of data seems to be a pretty good idea, it’s a good time to examine one particular important quality issue of print media: photos. While professionally printed photographs last generations, the slew of photo printers that’s out now doesn’t quite match up when it comes to durability. A photo you print at home, even on the best of personal photo printers, may last only a few years. Some popular Epson, Canon, and HP photo inks are only guaranteed to last one to two years. So if you’re planning on holding onto that 90th-birthday photo of Grandpa Mo, consider getting a professional print, and always use good-quality photo paper at home.

For more on this subject, see my upcoming article about the best methods for storing your data long-term, no matter what media you choose to do it with.

Related articles:

• (Not) Extending Vista Memory with a USB Device
• ZIP Up Files from the Command Line
• An Introduction to Rsync (part 1)
• An Introduction to Rsync (part 2)

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