What is JavaScript?
JavaScript is a programming language that makes websites interactive. When you click a button, submit a form, or see a popup — that's JavaScript in action.
Created in 1995, JavaScript has grown into the most popular programming language. Today, it runs on every browser, servers (Node.js), mobile apps, and more.
💡 Key insight
JavaScript is the only language that runs natively in every web browser. That makes it the universal language of the web.
Where Does JavaScript Run?
- In the Browser — Every modern browser has a JavaScript engine
- On the Server — Node.js runs JavaScript on servers
- In Apps — React Native, Electron, and more