Learn TypeScript Programming

Type-safe JavaScript: learn how TypeScript compiles to JS, set up locally, and master core language features.

Start Learning Try TypeScript Online
Tutorial Contents
Install TypeScript
TS Basics
TS Control Flow
TS Functions
TS Types
Additional Topics
Modules & Config

TypeScript Null & Undefined

let n: null = null;\nlet u: undefined = undefined;

Explanation

This example demonstrates core TypeScript concepts with concise code and plain-English guidance for readability.

TypeScript Programming Tutorial — Learn type-safe JavaScript with practical examples. Run TS online, install it locally, and master core features like types, interfaces, classes, generics, and modules. Human-written, SEO-friendly explanations ensure clarity and discoverability.

Frequently Asked Questions

Answers to common TypeScript getting-started questions

TypeScript is a superset of JavaScript that adds static types. It is compiled to plain JavaScript using the TypeScript compiler (tsc), so it runs wherever JavaScript runs.

You can use an online TypeScript compiler to write and run TS code directly in your browser. This is ideal for beginners to practice quickly.

Install Node.js first, then run: npm install -g typescript. Verify the installation using: tsc --version.

Yes. You can incrementally add TypeScript to existing JavaScript projects and configure the compiler to interoperate with JS files.