Welcome! This book will teach you about the Rust Programming Language. Rust is a systems programming language focused on three goals: safety, speed, and concurrency. It maintains these goals without having a garbage collector, making it a useful language for a number of use cases other languages aren’t good at: embedding in other languages, programs with specific space and time requirements, and writing low-level code, like device drivers and operating systems. It improves on current languages targeting this space by having a number of compile-time safety checks that produce no runtime overhead, while eliminating all data races. Rust also aims to achieve ‘zero-cost abstractions’ even though some of these abstractions feel like those of a high-level language. Even then, Rust still allows precise control like a low-level language would. This is Rust-101, a small tutorial for the Rust language. It is intended to be an interactive, hands-on course: I believe the only way to really learn a language is to write code in it, so you should be coding during the course. If you have any questions that are not answered here, check out the "Additional Resources" below. In particular, the IRC channel is filled with awesome people willing to help you! I spent lots of time there ;-) I will assume some familiarity with programming, and hence not explain the basic concepts common to most languages. Instead, I will focus on what makes Rust special.