Data Types

Rust is a systems programming language focused on speed, memory safety, and fearless concurrency — and because it is statically typed, every value has a known type at compile time.

Learn Data Types in our free Rust course — a beginner-friendly interactive lesson with worked examples, a practice exercise and a quick reference.

Part of the free Rust course at LearnCodingFast — hands-on lessons with examples you run in your browser, plus practice exercises and a quick quiz.

In this lesson you'll meet Rust's scalar types (integers, floats, booleans, chars) and its compound types (tuples and arrays), and learn how the compiler infers and checks them.

What You'll Learn in This Lesson

1️⃣ Scalar Types: Numbers, Booleans, and Chars

Scalar types represent a single value. Rust has four families: integers (whole numbers like i32 and u8 ), floating-point numbers (decimals like f64 ), booleans ( true / false ), and characters (a single Unicode value in single quotes). You can let Rust infer the type or annotate it explicitly with a colon.

The letter i or u tells you signed or unsigned, and the number tells you the bit width. When you don't annotate, integers default to i32 and floats to f64 .

2️⃣ Compound Types: Tuples and Arrays

Compound types bundle several values into one. A tuple holds a fixed number of values that can be different types, accessed by position ( .0 , .1 ). An array holds a fixed number of values that are all the same type, accessed by index ( [0] ). You can also destructure a tuple into separate names.

Both tuples and arrays have a fixed length known at compile time. For a growable list you'd reach for a Vec , which you'll meet later. Notice {' '} printed the whole array at once.

Your turn. Fill in the blanks marked ___ , then run it.

Write it yourself from the outline and run it with cargo run . You'll combine a tuple, destructuring, and an array.

📋 Quick Reference — Data Types

Practice quiz

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