What is Rust?

Rust is a general-purpose systems language stewarded by the Rust Foundation. It powers infrastructure tools (ripgrep, fd), cloud edge services, game engines, and WebAssembly modules.

Core characteristics

• Ownership model — each value has one owner; moves and borrows are checked at compile time
• No GC in safe code — destructors run when values go out of scope
• Zero-cost abstractions — iterators and generics compile to efficient machine code
• Algebraic enums — Option, Result, and custom enums with data

Typical build-run flow (local)

1. Write main.rs with fn main()
2. rustc main.rs or cargo run in a project
3. Run the native binary—no JVM required

Important interview questions and answers

1. Q: Is Rust garbage collected?
   A: No—ownership determines when memory is freed; optional patterns like Arc exist for shared ownership.
2. Q: Why is Rust hard for beginners?
   A: The borrow checker enforces rules other languages hide with GC or manual discipline.
3. Q: Rust vs C++?
   A: Both compile natively; Rust's safe subset prevents many C++ memory bugs at compile time.

Self-check

1. What file extension do Rust source files use?
2. Name one real-world tool written in Rust.