Did you know that movable books (including pop-ups) were originally made strictly for adults? It’s true; papercrafts are not just for kids!
I like to think that papercrafts are a part of movable book history, even though they may not be contained within a book. If anything, they take the art to a further level, breaking free of the bonds and limitations of books and cards. Although, I have to admit that it takes a different and highly respectable skill to be able to engineer the mechanics of a pop-up book.
If you have an hour to kill, take a look at this presentation, by Ellen Rubin (a.k.a. The Pop-Up Lady), of the history of movable books and paper engineering.