% The Rust Programming Language Has Moved
When The Rust Programming Language only had one edition, it was all hosted at
book/. Now that it has two, they are properly namespaced under
first-edition/ and second-edition/.
You've found this page because you have a link to the older URL structure; you probably want to visit first-edition/ if you need the exact older page; if you're trying to learn Rust, checking out the second edition might be a better choice.