Daisky wants to store files in a way that will make them available to future generations.

People worry a lot about archiving digital files for long periods of time. The concern is legitimate. I wouldn't go as far as the people who insist that burned CDs and DVDs (the kind you buy blank and write files to on your PC's drive) last for only two to five years. But it is true that these burnable discs use unstable light-sensitive dyes, and will probably not be readable in 20 years. And if they are, will you still have optical drives for reading them? Or software that can read the files?

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It's impossible to answer any of these questions definitively at this time. But a few precautions and educated guesses will improve the likelihood that your great-grandchildren will enjoy your wedding photos.

Let's consider software first.

Stick with popular file formats that everyone uses and that aren't controlled by one company. The more applications support a format now, the greater the chance that someone will support it in 50 years. And just to be safe, if it’s possible, save the same files in more than one format.

Save and store documents in .docx, .doc, .pdf, and .html. For photos, go with .jpg and .png. For music, .mp3 and .wav.

Video is a real problem, because the format standards aren’t real standards. A device that can play one .avi file may not be able to play another. Your best bet is probably to burn the files to video DVDs or Blu-ray discs.

Which brings us to the next question: On what media should you save these files?

First, keep them on your main internal storage--be that a hard drive, SSD, or cloud service. And make sure the files are included in your regular daily backup routine.

Then, for added protection, burn them to special, archival optical discs. Your best bet here are probably M-Discs. Burning an M-Disc is a bit like carving the bits in granite, and the company claims that they'll last for 1,000 years.

Is that claim accurate? I can’t tell you for another 999 years. But I've seen government test reports suggesting that M-Discs are far more stable than other burnable discs.

You need a special drive to burn M-Discs. But once burned, they can be read on any DVD drive (Blu-ray M-Discs are on the way).

I can't say for sure whether optical drives will be available in the future, but I suspect that they will be—even if no longer common—for a very long time. If enough people have discs to read, there will be profits in making drives. You can still buy a new floppy drive, VHS player, or turntable, even one that plays 78's and 45's.

Read the original forum discussion.