What is JavaScript?

Discover why JavaScript was created and what role it plays on every web page you visit.

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The web was frozen in place

In the early 1990s, web pages could only display text and images. Clicking a button required a full page reload from the server. There was no way to react instantly to what the user did — no dropdown menus, no form checking, no animations. Brendan Eich created JavaScript in 1995 at Netscape to solve this exact problem: give web pages the ability to respond to user actions right inside the browser, without waiting for the server.

Think of it this way: Think of a web page like a printed poster on a wall. HTML is the paper and ink — it gives the poster its structure and words. CSS is the color scheme and layout — it makes the poster look good. But a poster can't do anything when you touch it. JavaScript is what turns that poster into a touchscreen: now tapping, swiping, and typing actually make things happen.

Web Standard

JavaScript follows a standard called ECMAScript, maintained by an international committee (TC39). When you hear 'ES6' or 'ES2015,' that refers to the 6th edition of this standard — a major update that added features like `let`, `const`, arrow functions, and more. Every browser maker implements the same standard so your code works everywhere.

Learn more on MDN

JavaScript overview