Did you know?

[An old bloke]

I certainly didn't until I read it just now.

'... the issue of data corruption is even more urgent ... In warm, humid conditions, CDs and DVDs experience literal rot ... If you're lucky, they'll last fifteen years. Some technicians say six. There there is "bit rot": digital files degarsd as they lose their magnetic orientation, and the magnetic bit strength on hard drives gradually fades as well. Technicians advise re copying to a new format every five years. They point out that the computer industry is dedicated to planned obsolescence; one writer recommended that if you really want to preserve document, use paper and ink.' (Ink; Culture, Wonder, and Our Relationship with the Written Word, Ted Bishop, 2014, Toronto, Penguin, pages 247-248)

[silverlifter]

Bit rot is a thing. But I don't necessarily agree that the (only) answer is paper and ink, especially considering the sheer volume of digital data created every day.

Any important data should always be in a state of constant but incredibly slow migration; from disk to disk, or even ocassionally format to format (unless the format is integral to the data). In a past life, I was responsible for the management of government records. It is a fascinating and evolving field.

[Ole Juul]

I've got 5 1/4" floppies from the 80's that read like new. This is expected.

[ChrisJ]

A few years ago I was visiting the EMI Music Archives and was chatting with one of their Archivists

The biggest issues were not about storing and looking after Acetates & Vinyl records from the early 20th century , rather it was dealing with the proliferation of digital formats from the 1980's onwards, Just having the storage medium is just the beginning , you also need to maintain and archive the playback systems, both hardware , operating systems and software . They had less confidence about preserving obsolete digital formats from the 2000's than musical recordings from the 1920s . You couple this with the issue of data degradation and the problems mount

[Pendragon]

I certainly didn't until I read it just now.

'... the issue of data corruption is even more urgent ... In warm, humid conditions, CDs and DVDs experience literal rot ... If you're lucky, they'll last fifteen years. Some technicians say six. There there is "bit rot": digital files degarsd as they lose their magnetic orientation, and the magnetic bit strength on hard drives gradually fades as well. Technicians advise re copying to a new format every five years. They point out that the computer industry is dedicated to planned obsolescence; one writer recommended that if you really want to preserve document, use paper and ink.' (Ink; Culture, Wonder, and Our Relationship with the Written Word, Ted Bishop, 2014, Toronto, Penguin, pages 247-248)

I had read about optical disks delaminating or otherwise going bad as far back as the late 1990s. What you say definitely has merit, though. I have DVDs that are over 20 years old, and are still perfectly readable. The same for some CDs that are even older, so data corruption after a few years is not inevitable. M-Disc makes archival-quality DVD and Blu-Ray media, as does Mitsui (MAM-A Gold discs). Mind which marker pens you use to label the discs, as some can damage the media.

SSDs, both in the form of external USB-connected drives and "thumb drives", are widely used to make backups. These are less than ideal for long-term storage, as the memory cells gradually lose their charge. Hard drives work much better for disk-based backups and long-term storage. If they are exposed to extremes of temperature, they can become unreadable, something to keep in mind. In my experience, optical disks are better still, although they take longer to write and are somewhat limited in capacity. Cloud based backups are perhaps the best of all, as the backup exists offsite. If your house gets disintegrated by a tornado, swept away by a flood, or incinerated by a wildfire, your data is still safe.

All of the above is assuming that any backups made are truly backups (i.e. at least two copies of the data exist on different devices). Copying data from your computer to a backup device and deleting the original does not count. That is simply moving data from one location to another with no backup existing.

Hope this helps.