JavaScript Guides

Welcome to the JavaScript User Guide. This section is designed to help you build a solid understanding of JavaScript, starting with core concepts and gradually introducing more advanced ideas.

Getting started

New to JavaScript? Start here! Learn what JavaScript is and how to run JavaScript code.

Introduction to JavaScript

Running JavaScript

Variables and values

Learn how to store and work with data using variables, operators, and values.

Variables and Values

Data Types

Numbers

Booleans

Strings, arrays, and objects

Explore JavaScript's fundamental data structures: strings for text, arrays for ordered lists, and objects for key-value pairs.

Strings

Arrays

Objects (Plain Objects)

JSON

Rest and Spread

Control flow

Learn how to make decisions and repeat actions in your programs using conditionals and loops.

Conditionals

Loops

Errors and Control Flow

Functions and scope

Master function creation, parameters, scope, and how to organize code into reusable blocks.

Functions

Callback functions

Scope and Closures

Modules

Object-oriented programming

Learn how to create classes, work with instances, and use inheritance to build robust programs.

Introduction to Object-Oriented JavaScript

Classes and Instances

Methods

Encapsulation

Inheritance

Static Properties and Methods

Classes vs Plain Objects

When to Use OOP

Asynchronous programming

Master asynchronous JavaScript with promises and async/await to handle time-based operations.

Asynchronous JavaScript

Callbacks (Historical Context)

Promises

async/await

Putting it together

See how all these concepts work together in real JavaScript programs.

Putting It Together

JavaScript Quirks