Learn JavaScript

An in-depth course on the basics of JavaScript.

 

Welcome to Learn JavaScript!

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An in-depth course on the basics of JavaScript.

Introduction to JavaScript

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A brief history of JavaScript and an overview of its basic rules.

Data types and structures

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The basic "primitive" data types of JavaScript.

Numbers

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Learn how to use JavaScript's number data type.

Strings

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Learn how to use JavaScript's string data type.

Booleans

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Learn how to use JavaScript's boolean data type.

Null and undefined values

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Learn how to use JavaScript's null and undefined data types.

BigInt

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Learn how to use JavaScript's BigInt data type.

Symbols

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Learn how to use JavaScript's symbol data type.

Variables

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Learn how to use JavaScript variables.

Comparison operators

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Learn how to use comparison operators.

Control flow

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Learn about JavaScript's control flow.

Introduction to functions

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An introduction to JavaScript functions.

Function expressions

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An introduction to JavaScript function expressions.

The "new" keyword

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Call functions using the `new` keyword to create objects.

The "return" keyword

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Use the `return` keyword to get more out of your functions.

The "this" keyword

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Use the `this` keyword to work with the context your function executes in.

Introduction to objects

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Introduction to JavaScript objects.

Property accessors

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Learn how to set, alter, and access the properties of an object.

Prototypal inheritance

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JavaScript objects and prototypal inheritance.

Property descriptors

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Use property descriptors to configure your JavaScript objects.

Indexed collections

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Learn how to use indexed collections such as arrays.

Keyed collections

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Learn how to use keyed collections such as maps and sets.

Introduction to classes

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Learn how to use classes in JavaScript.

Extend classes

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The `extends` keyword lets you create subclasses of existing classes.

Class fields and methods

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Use class fields and methods to add properties to your classes.

Static initialization blocks

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Use static initialization blocks to set or alter static fields.

Appendix

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Additional information that might be helpful on your JavaScript journey.