Learn JavaScript Programming

Master JavaScript from basics to advanced concepts with clear explanations and practical examples.

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Tutorial Contents
Getting Started
Fundamentals
Functions & Data
Browser APIs
Advanced

Variables: var, let, const

Use let for reassignable, block-scoped variables and const for values that shouldn’t be reassigned. Avoid var in modern code; it’s function-scoped and can cause unexpected behavior due to hoisting.

Tip: const prevents reassigning the variable binding but does not make objects immutable. You can still modify properties of a const object.

let count = 0;
count++;
const API_URL = 'https://api.example.com';
// var is function-scoped
var old = 'legacy';
}

Frequently Asked Questions

JavaScript is used to build interactive websites, single-page applications, and servers with Node.js. It controls the DOM, handles events, and communicates with APIs.

Basic HTML and CSS knowledge helps, especially for DOM manipulation, but you can start learning JavaScript directly and pick up HTML/CSS basics along the way.

With regular practice, basics can be learned in 2–4 weeks. Mastery of ES6+, asynchronous programming, and frameworks typically takes a few months of consistent learning.

A modern browser (Chrome/Firefox) and a code editor (VS Code). Optionally, Node.js for running JavaScript outside the browser and using npm packages.
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Master JavaScript with Our Beginner-Friendly Tutorial

Learn modern JavaScript step by step with examples you can run and modify. Build interactive web pages, handle events, manipulate the DOM, and work with APIs confidently.

What You'll Learn

  • Variables, data types, and operators
  • Functions and array methods
  • Objects, classes, and prototypes
  • DOM and events
  • JSON and API calls
  • Promises and async/await
  • Modules and modern tooling
  • Best practices and tips

Our tutorial is crafted for clarity, SEO-friendly readability, and a smooth learning experience on mobile devices.

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