https://en.wikipedia.org/wiki/Dead_Sea_Scrolls

> Dating from the 3rd century BCE to the 1st century CE, the Dead Sea Scrolls include the oldest surviving manuscripts of entire books later included in the various Jewish and Christian biblical canons, including deuterocanonical manuscripts from late Second Temple Judaism, as well as extrabiblical books. As such, they cast new light on the emergence of Rabbinic Judaism and of Christianity, and their relationship with Jewish religious traditions.

One could similarly imagine a set of M-Discs from today that would be rediscovered 1000 years from now that could prove similarly useful to the people of the future thanks to data on them that has been preserved unaltered since today until then on that set of M-Discs.