JavaScript Tutorial

1. JavaScript Introduction

What JavaScript is, where it runs (browser and Node.js), and how the language has evolved since ES2015.

2. JavaScript Syntax and Variables

let/const vs var, primitive types, template literals, arrays, objects, destructuring and spread/rest.

3. Functions, Closures and this

Function declarations vs expressions vs arrow functions, closures, this binding, and prototypes.

4. Error Handling

try/catch/finally, custom Error classes, and handling errors in async/await and Promise chains.

5. Modules: import and export

Named vs default exports, re-exporting, and code-splitting with dynamic import().

6. Async JavaScript

The event loop, Promises, async/await, Promise.all, and common async pitfalls to avoid.

7. The DOM in Depth

Selecting and traversing elements, creating/modifying nodes programmatically, and event delegation.

8. Testing with Jest

Writing test files with describe/test/expect, matchers, mocking dependencies, and setup/teardown hooks.

9. JavaScript Interview Questions

Real JavaScript interview questions and answers covering closures, this, the event loop and hoisting.