[mharig]

0. Buy archive paper and a printer and ink/toner that are certified for 200 years. Print out the specs of all the file formats you store. And of the filesystem, too.

1. If the data can be in the open, use archive.org. They assume a cost of 2 USD/GB, so please donate an appropriate amount.

2. As other commenters proposed, use M-DISC. But you must deposit M-Disc reader(s) and the hardware to drive those, and better be redundant.

3. Use endurance SDCards. They can be read (and written) by just 4 wires. Use UDF as filesystem. Print out the SDCard specs. Make sure you and your descendants put power to the SDCards every 5 years or so to refresh the cells.

[hulitu]

> Use endurance SDCards.

"As a computer, i find your trust in technology, amusing"

[mharig]

Personally, I have very good experiences with FLASH, and very bad experiences with spinning disc HDDs, CDROMs, DVDs.

IMHO, all long term cold storage is not reliable. Better to go with mid-term storage, and not just using one technology. For really important data, I would go for LTO AND BD AND SD card and maybe some paid online storage.

[hulitu]

Flash data retention is about 10 years. And with ROHS everything is a smoking gun.