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JS Tutorial

JS HOME JS Introduction JS Where To JS Output JS Statements JS Syntax JS Comments JS Variables JS Let JS Const JS Operators JS Arithmetic JS Assignment JS Data Types JS Functions JS Objects JS Object Properties JS Object Methods JS Object Display JS Object Constructors JS Events JS Strings JS String Methods JS String Search JS String Templates JS Numbers JS BigInt JS Number Methods JS Number Properties JS Arrays JS Array Methods JS Array Search JS Array Sort JS Array Iteration JS Array Const JS Dates JS Date Formats JS Date Get Methods JS Date Set Methods JS Math JS Random JS Booleans JS Comparisons JS If Else JS Switch JS Loop For JS Loop For In JS Loop For Of JS Loop While JS Break JS Iterables JS Sets JS Set Methods JS Maps JS Map Methods JS Typeof JS Type Conversion JS Destructuring JS Bitwise JS RegExp JS Precedence JS Errors JS Scope JS Hoisting JS Strict Mode JS this Keyword JS Arrow Function JS Classes JS Modules JS JSON JS Debugging JS Style Guide JS Best Practices JS Mistakes JS Performance JS Reserved Words

JS Versions

JS Versions JS 2009 (ES5) JS 2015 (ES6) JS 2016 JS 2017 JS 2018 JS 2019 JS 2020 JS 2021 JS 2022 JS 2023 JS 2024 JS IE / Edge JS History

JS Objects

Object Definitions Object Prototypes Object Methods Object Properties Object Get / Set Object Protection

JS Functions

Function Definitions Function Parameters Function Invocation Function Call Function Apply Function Bind Function Closures

JS Classes

Class Intro Class Inheritance Class Static

JS Async

JS Callbacks JS Asynchronous JS Promises JS Async/Await

JS HTML DOM

DOM Intro DOM Methods DOM Document DOM Elements DOM HTML DOM Forms DOM CSS DOM Animations DOM Events DOM Event Listener DOM Navigation DOM Nodes DOM Collections DOM Node Lists

JS Browser BOM

JS Window JS Screen JS Location JS History JS Navigator JS Popup Alert JS Timing JS Cookies

JS Web APIs

Web API Intro Web Forms API Web History API Web Storage API Web Worker API Web Fetch API Web Geolocation API

JS AJAX

AJAX Intro AJAX XMLHttp AJAX Request AJAX Response AJAX XML File AJAX PHP AJAX ASP AJAX Database AJAX Applications AJAX Examples

JS JSON

JSON Intro JSON Syntax JSON vs XML JSON Data Types JSON Parse JSON Stringify JSON Objects JSON Arrays JSON Server JSON PHP JSON HTML JSON JSONP

JS vs jQuery

jQuery Selectors jQuery HTML jQuery CSS jQuery DOM

JS Graphics

JS Graphics JS Canvas JS Plotly JS Chart.js JS Google Chart JS D3.js

JS Examples

JS Examples JS HTML DOM JS HTML Input JS HTML Objects JS HTML Events JS Browser JS Editor JS Exercises JS Quiz JS Website JS Interview Prep JS Bootcamp JS Certificate

JS References

JavaScript Objects HTML DOM Objects


JavaScript Examples


What can JavaScript do?

Examples Explained


Where to Insert JavaScript

Where to Explained


JavaScript Output

Output Explained


JavaScript Syntax

Syntax Explained



JavaScript Statements

Statements Explained


JavaScript Comments

Comments Explained


JavaScript Variables

Variables Explained


JavaScript Arithmetic

Arithmetic Explained


JavaScript Assignment

Assignment Explained


JavaScript String Concatenation

Concatenation Explained


JavaScript Data Types

Data types Explained


JavaScript Objects

Objects Explained


JavaScript Functions

Functions Explained


JavaScript Events

Events Explained


JavaScript Strings

Strings Explained


JavaScript Numbers

Numbers can be written with or without decimals Extra large or extra small numbers can be written with exponent notation Number are considered accurate only up to 15 digits Floating point arithmetic is not always 100% accurate But it helps to multiply and divide by 10 Adding two numbers results in a new number Adding two numeric strings results in a concatenated string Adding a number and a numeric string also results in a concatenated string Adding a numeric string and a number also results in a concatenated string Common mistake when adding strings and numbers 1 Common mistake when adding strings and numbers 2 JavaScript will try to convert strings to numbers when dividing JavaScript will try to convert strings to numbers when multiplying JavaScript will try to convert strings to numbers when subtracting JavaScript will NOT convert strings to numbers when adding A number divided by a string is NaN (Not a Number) A number divided by a numeric string is a number The global JavaScript function isNaN() returns if a value is a number Using NaN in a mathematical operation will always return NaN Using NaN in a mathematical string operation will concatenate NaN NaN (Not a Number) is a number (Yes! typeof NaN returns number) Infinity is returned if you calculate a number outside the largest possible number Division by zero also generates Infinity Infinity is a number (typeof Infinity returns number) Constants, preceded by 0x, are interpreted as hexadecimal The toString() method can output numbers as hex, octal, and binary Numbers can be objects Numbers and objects cannot be safely compared Objects and objects cannot be safely compared

Numbers Explained


JavaScript Number Methods

Numbers Methods Explained


JavaScript Maths

Maths Explained


JavaScript Random

Random Explained


JavaScript Dates

Dates Explained


JavaScript Arrays

Arrays Explained


JavaScript Array Methods

Array Methods Explained


JavaScript Array Sort

Array Sort Explained


JavaScript Array Iteration

Array Iteration Explained


JavaScript Type Conversion

Type Conversion Explained


JavaScript Booleans

Booleans Explained


JavaScript Comparisons

Comparisons Explained


JavaScript Conditionals

Conditionals Explained


JavaScript Loops

Loops Explained


JavaScript Error Handling

Errors Explained


JavaScript Regular Expressions


JavaScript Objects

Objects Explained


JavaScript Object Properties

Object Properties Explained


JSON Objects

JSON Object Properties Explained


JSON Arrays

JSON Arrays Explained


JSON Parse

JSON Parse Explained


JSON Stringify

JSON Stringify Explained


JSON PHP

JSON PHP Explained


JSON HTML

JSON HTML Explained


JSON JSONP

JSON JSONP Explained


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