JavaScript Tutorial

JavaScript (JS) is a lightweight, interpreted (JIT-compiled), dynamically typed language. It was created by Brendan Eich at Netscape in 1995, and is standardised as ECMAScript. It runs in every browser, and on servers through Node.js.

Your First Program

console.log("Hello, JavaScript!");

Adding JavaScript to a Page

<!-- Internal -->
<script>
    console.log("Page loaded");
</script>

<!-- External (recommended) -->
<script src="app.js" defer></script>

Open the browser's developer console (F12 → Console) to see console.log output.

HTML, CSS and JavaScript