Really, it's hard to picture a data format that's pretty much the standard for the era ever become totally unreadable, so long as the data is intact.
O rly? Know that ubiquitous Save symbol? How many under 18 have ever seen a real floppy disk? That aside, I second the M-Disc in a player with autoplay; the disc will survive, a player built to last may also survive.
We declare the names of all variables and functions. Yet the Tao has no type specifier.