% `unsafe` There is a new edition of the book and this is an old link. > Rust has a second language hiding out inside of it, unsafe Rust, which does not enforce memory safety guarantees. --- Here are the relevant sections in the new and old books: * **[in the current edition: Ch 19.01 — Unsafe Rust][2]** * [The Rustonomicon, The Dark Arts of Advanced and Unsafe Rust Programming][3] * [In the first edition: Ch 3.36 — `unsafe`][1] [1]: https://doc.rust-lang.org/1.30.0/book/first-edition/unsafe.html [2]: ch19-01-unsafe-rust.html [3]: ../nomicon/index.html