[zanny]

> How much of today's electronic info would it be possible to read in 550 years?

If the encoding standards are non-proprietary and you either kept data stored in a linear binary format compatible with modern persistent file encoding, or just translated the works over time, then all of them.

All ODF / PDF files should be readable in 500 years. You can back them up for minimal cost in facilities around the world, and since the specifications to render them are completely open standards, you can (at worst) write software to interpret them again if necessary.

When dead tree rots, it rots. You had to (painstakingly) transcribe dead tree papers over and over to insure they don't degrade. We already have ROM archive tape standards meant to last millenia in the absence of environmental decay of their containments.

[smsm42]

They should be, but that assumes docs about what PDF format is survive, and they'd know how to read media on which PDF is stored (which is much more scarcely documented - do you know how your HD encodes data on physical level?) and have compatible hardware or know how to build one. That's a lot of hops and failure on any of them may render the whole chain unworkable.

And, of course, magnetic media can degrade and be physically destroyed as well as dead tree media. There are standards for long-term storage, but most of the info is not stored that way. We find most routine documents from thousand years ago written on paper, cloth, leather, bark, papyrus, etc. but today's routine information would never survive even a century, only specially preserved data - a tiny minority of it - would.