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What is TypeScript?

TypeScript is a superset of JavaScript that adds static type checking. It was created by Microsoft and compiles to plain JavaScript.

Why TypeScript?

Type Safety: Catch errors at compile time, not runtime
Better IDE Support: Autocomplete, refactoring, and navigation
Improved Code Quality: Self-documenting code with types
Framework Ready: Essential for Angular, React, and Vue

Installing TypeScript

npm install -g typescript
# Or use npx
tsc --version

Your First TypeScript File

Create a file hello.ts:

function greet(name: string): string {
  return `Hello, ${name}!`;
}

const message = greet("TypeScript");
console.log(message);

Compiling TypeScript

tsc hello.ts
# This creates hello.js

TypeScript vs JavaScript

TypeScript adds:

Type annotations
Interfaces
Classes with access modifiers
Enums
Generics
And much more!

Example Code

Write a simple TypeScript function that greets a user

// Write a function that takes a name (string) and returns a greeting
function greet(name: string): string {
  // Your code here
}

// Test your function
console.log(greet("TypeScript"));

Expected Output:

Hello, TypeScript!

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