Js Intro — Free Javascript Tutorial
Learn Js Intro in Javascript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
TL;DR: Learn Js Intro in Javascript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
Written & reviewed by the Syllab.in Academic Team (CBSE/NCERT subject experts) · Updated
Js Intro in Javascript
JavaScript (JS) is the only programming language that runs natively in every web browser. It makes websites interactive — buttons that respond, forms that validate, animations, real-time updates, games, and much more. Together with HTML and CSS, it forms the complete front-end trinity. Without JavaScript, the web would be static documents.
Brendan Eich created JavaScript in 1995 in just 10 days while working at Netscape Communications. It was originally called "Mocha," then "LiveScript," and finally "JavaScript" for marketing reasons (to capitalize on Java's popularity). Despite its name, JavaScript is completely unrelated to Java. JavaScript 1.5 (2000) became ECMAScript standard, and ES6/ES2015 (2015) modernized the language with classes, arrow functions, and promises.
JavaScript's evolution shows explosive growth: from a simple browser scripting language to a complete programming ecosystem. Key milestones: jQuery (2006) simplified DOM manipulation, Node.js (2009) brought JS to servers, React (2013) revolutionized front-end development, async/await (2017) modernized asynchronous programming. Today, JavaScript powers everything from simple web pages to complex applications like Figma and Discord.
JavaScript is used in React, Vue, Angular (front-end frameworks), Node.js (backend), React Native (mobile apps), Electron (desktop apps), and serverless computing (AWS Lambda). Popular libraries: D3.js (data visualization), TensorFlow.js (AI in browsers), Express.js (server framework), Stripe and PayPal (payment integration). JavaScript runs on billions of devices.
In India, Ja
Js Intro — Syntax
// In HTML file (inside <script> tag):
<script>
console.log("Hello!"); // browser console
alert("Popup!"); // browser alert
</script>
// Or in external file: <script src="app.js"></script>
Learn Js Intro step by step with Syllab's free interactive Javascript tutorial — runnable code examples, practice exercises and instant AI feedback, all free with no signup. Explore the full Javascript course →