What is TypeScript?

What You'll Learn

What TypeScript is
Why use TypeScript
TypeScript vs JavaScript

TypeScript is a strongly typed superset of JavaScript developed by Microsoft. It compiles to plain JavaScript and adds optional static typing.

Key Benefits

Benefit	Description
Type Safety	Catch errors at compile time
Better IDE Support	Autocomplete, refactoring
Self-Documenting	Types serve as documentation
Scalability	Easier to maintain large codebases

Example

code.tsTypeScript

// JavaScript
function greet(name) {
  return "Hello, " + name;
}

// TypeScript
function greet(name: string): string {
  return "Hello, " + name;
}

greet(123); // Error: Argument of type 'number' is not assignable

TypeScript Compiles to JavaScript

code.tsTypeScript

// TypeScript
const add = (a: number, b: number): number => a + b;

// Compiles to JavaScript
const add = (a, b) => a + b;