This is something I worry about regardless of the specific storage media type. I have all my photos on my hard drive backed up onto a two drive mirrored NAS de

This is something I worry about regardless of the specific storage media type. I have all my photos on my hard drive backed up onto a two drive mirrored NAS device and uploaded to a third party cloud based backup service. Many of them also have low resolution versions posted on Facebook and Flickr. But I still worry that in 70 years no trace will be left of these photos. Printed photos sitting in a photo book with each photo in its own plastic sleeve that is stored in a dry location away from light won't last forever, but it will probably last 70 years. My digital photos have to constantly be backed up and copied over time. Cloud backup services and social media websites will go out of business. Both the drives in my NAS will eventually fail, along with the drive in my PC. For these photos to survive, someone has to perpetually do work to keep them around. Sometimes I wonder if, despite the fact that camera phones means we take an absolutely immense amount of pictures relative to other periods of time, if in 100 years there will be more photos from 1985-1995 than 2005-2015, just because the older photos were printed and stored in photo books. At some point I should probably print my most important photos.