Or cultural nuances of language. Imagine four thousand years from now, if someone read that some guy named “art_rocks” jumped in his Jaguar and went to the arena to watch the Giants and Lions battle. The meaning then may be much different than what we understand now simply because of cultural changes in terminology.
Eighty years ago, everyone wanted to be gay, and in Britain we’d go outside and enjoy a fag!
Fifty years ago being bad would get you locked up. Twenty five years ago, being bad was about as good as you can get. Now it’s back to being thrown in jail...