Learn the difference between var, let, and const, and master JavaScript's primitive data types in this beginner-friendly tutorial.
Tutorial series
Javascript Fundamentals
10 tutorials — follow in order for the best learning path.
- JavaScript Fundamentals: Variables and Types
- Functions and Scope in JavaScript
Learn how to define functions in JavaScript, understand variable scope (global, function, and block scope), and master closures.
- JavaScript Fundamentals: Objects and Arrays
Master objects and arrays in JavaScript—learn how to create, manipulate, and use these fundamental data structures effectively.
- JavaScript Fundamentals: Control Flow
Master control flow in JavaScript with if/else statements, switch cases, and loops. Learn how to direct the execution path of your programs.
- JavaScript Fundamentals: Classes in JavaScript
Learn how to create and use classes in JavaScript, including constructors, methods, inheritance, and private fields.
- Error handling in JavaScript: try/catch and beyond
Handle errors in JavaScript with try/catch, custom error classes, async error patterns, and debugging tactics that keep production apps healthy.
- Working with the DOM
Learn how to select, create, modify, and remove DOM elements, handle events, and build interactive web pages with JavaScript.
- Callbacks, Promises, and async/await
Learn how JavaScript handles asynchronous operations from callbacks to modern async/await syntax.
- JavaScript Fundamentals: ES Modules: import and export
Learn how to use ES Modules (import/export) in JavaScript to organize code into reusable modules.
- JavaScript Symbols and Iterators: Custom Iterables Guide
Master JavaScript symbols iterators and the iterator protocol. Learn well-known symbols, create custom iterables, and use for...of loops effectively.