TypeScript gives you precise control over what your variables can hold. Think of types as contracts you create with your code - you're telling TypeScript exactly what shape the data should take. This prevents those annoying runtime bugs where a number suddenly becomes a string when you least expect it.
Primitive Types
TypeScript comes with a set of built-in primitive types. `string` holds text, `number` holds numeric values, `boolean` holds true/false values, `null` and `undefined` represent emptiness, and `void` represents no return value. These are the basic building blocks of any TypeScript program.
let name: string = "John";
let age: number = 30;
let isActive: boolean = true;
let nullValue: null = null;
let undefinedValue: undefined = undefined;
let noReturn: void = undefined;
// Arrays
let fruits: string[] = ["apple", "banana", "cherry"];
let scores: number[] = [85, 90, 95];
// Tuples (fixed-length arrays)
let person: [string, number] = ["Alice", 25];