- Javascript Basics Tutorial
- Javascript - Home
- JavaScript - Overview
- JavaScript - Features
- JavaScript - Enabling
- JavaScript - Placement
- JavaScript - Syntax
- JavaScript - Hello World
- JavaScript - Console.log()
- JavaScript - Comments
- JavaScript - Variables
- JavaScript - let Statement
- JavaScript - Constants
- JavaScript - Data Types
- JavaScript - Type Conversions
- JavaScript - Strict Mode
- JavaScript - Reserved Keywords
- JavaScript Operators
- JavaScript - Operators
- JavaScript - Arithmetic Operators
- JavaScript - Comparison Operators
- JavaScript - Logical Operators
- JavaScript - Bitwise Operators
- JavaScript - Assignment Operators
- JavaScript - Conditional Operators
- JavaScript - typeof Operator
- JavaScript - Nullish Coalescing Operator
- JavaScript - Delete Operator
- JavaScript - Comma Operator
- JavaScript - Grouping Operator
- JavaScript - Yield Operator
- JavaScript - Spread Operator
- JavaScript - Exponentiation Operator
- JavaScript - Operator Precedence
- JavaScript Control Flow
- JavaScript - If...Else
- JavaScript - While Loop
- JavaScript - For Loop
- JavaScript - For...in
- Javascript - For...of
- JavaScript - Loop Control
- JavaScript - Break Statement
- JavaScript - Continue Statement
- JavaScript - Switch Case
- JavaScript - User Defined Iterators
- JavaScript Functions
- JavaScript - Functions
- JavaScript - Function Expressions
- JavaScript - Function Parameters
- JavaScript - Default Parameters
- JavaScript - Function() Constructor
- JavaScript - Function Hoisting
- JavaScript - Self-Invoking Functions
- JavaScript - Arrow Functions
- JavaScript - Function Invocation
- JavaScript - Function call()
- JavaScript - Function apply()
- JavaScript - Function bind()
- JavaScript - Closures
- JavaScript - Variable Scope
- JavaScript - Global Variables
- JavaScript - Smart Function Parameters
- JavaScript Objects
- JavaScript - Number
- JavaScript - Boolean
- JavaScript - Strings
- JavaScript - Arrays
- JavaScript - Date
- JavaScript - DataView
- JavaScript - Math
- JavaScript - RegExp
- JavaScript - Symbol
- JavaScript - Sets
- JavaScript - WeakSet
- JavaScript - Maps
- JavaScript - WeakMap
- JavaScript - Iterables
- JavaScript - Reflect
- JavaScript - TypedArray
- JavaScript - Template Literals
- JavaScript - Tagged Templates
- Object Oriented JavaScript
- JavaScript - Objects
- JavaScript - Classes
- JavaScript - Object Properties
- JavaScript - Object Methods
- JavaScript - Static Methods
- JavaScript - Display Objects
- JavaScript - Object Accessors
- JavaScript - Object Constructors
- JavaScript - Native Prototypes
- JavaScript - ES5 Object Methods
- JavaScript - Encapsulation
- JavaScript - Inheritance
- JavaScript - Abstraction
- JavaScript - Polymorphism
- JavaScript - Destructuring Assignment
- JavaScript - Object Destructuring
- JavaScript - Array Destructuring
- JavaScript - Nested Destructuring
- JavaScript - Optional Chaining
- JavaScript - Global Object
- JavaScript - Mixins
- JavaScript - Proxies
- JavaScript Versions
- JavaScript - History
- JavaScript - Versions
- JavaScript - ES5
- JavaScript - ES6
- ECMAScript 2016
- ECMAScript 2017
- ECMAScript 2018
- ECMAScript 2019
- ECMAScript 2020
- ECMAScript 2021
- ECMAScript 2022
- JavaScript Cookies
- JavaScript - Cookies
- JavaScript - Cookie Attributes
- JavaScript - Deleting Cookies
- JavaScript Browser BOM
- JavaScript - Browser Object Model
- JavaScript - Window Object
- JavaScript - Document Object
- JavaScript - Screen Object
- JavaScript - History Object
- JavaScript - Navigator Object
- JavaScript - Location Object
- JavaScript - Console Object
- JavaScript Web APIs
- JavaScript - Web API
- JavaScript - History API
- JavaScript - Storage API
- JavaScript - Forms API
- JavaScript - Worker API
- JavaScript - Fetch API
- JavaScript - Geolocation API
- JavaScript Events
- JavaScript - Events
- JavaScript - DOM Events
- JavaScript - addEventListener()
- JavaScript - Mouse Events
- JavaScript - Keyboard Events
- JavaScript - Form Events
- JavaScript - Window/Document Events
- JavaScript - Event Delegation
- JavaScript - Event Bubbling
- JavaScript - Event Capturing
- JavaScript - Custom Events
- JavaScript Error Handling
- JavaScript - Error Handling
- JavaScript - try...catch
- JavaScript - Debugging
- JavaScript - Custom Errors
- JavaScript - Extending Errors
- JavaScript Important Keywords
- JavaScript - this Keyword
- JavaScript - void Keyword
- JavaScript - new Keyword
- JavaScript - var Keyword
- JavaScript HTML DOM
- JavaScript - HTML DOM
- JavaScript - DOM Methods
- JavaScript - DOM Document
- JavaScript - DOM Elements
- JavaScript - DOM Forms
- JavaScript - Changing HTML
- JavaScript - Changing CSS
- JavaScript - DOM Animation
- JavaScript - DOM Navigation
- JavaScript - DOM Collections
- JavaScript - DOM Node Lists
- JavaScript Miscellaneous
- JavaScript - Ajax
- JavaScript - Async Iteration
- JavaScript - Atomics Objects
- JavaScript - Rest Parameter
- JavaScript - Page Redirect
- JavaScript - Dialog Boxes
- JavaScript - Page Printing
- JavaScript - Validations
- JavaScript - Animation
- JavaScript - Multimedia
- JavaScript - Image Map
- JavaScript - Browsers
- JavaScript - JSON
- JavaScript - Multiline Strings
- JavaScript - Date Formats
- JavaScript - Get Date Methods
- JavaScript - Set Date Methods
- JavaScript - Modules
- JavaScript - Dynamic Imports
- JavaScript - BigInt
- JavaScript - Blob
- JavaScript - Unicode
- JavaScript - Shallow Copy
- JavaScript - Call Stack
- JavaScript - Reference Type
- JavaScript - IndexedDB
- JavaScript - Clickjacking Attack
- JavaScript - Currying
- JavaScript - Graphics
- JavaScript - Canvas
- JavaScript - Debouncing
- JavaScript - Performance
- JavaScript - Style Guide
- JavaScript Useful Resources
- JavaScript - Questions And Answers
- JavaScript - Quick Guide
- JavaScript - Functions
- JavaScript - Resources
Enabling JavaScript in Browsers
Enabling JavaScript
All modern browsers come with built-in support for JavaScript, and it has enabled JavaScript by default. Frequently, you may need to enable or disable this support manually. This chapter explains how to turn JavaScript support on and off in your browsers: Chrome, Microsoft Edge, Firefox, Safari, and Opera.
JavaScript in Chrome
Here are the steps to turn on or turn off JavaScript in Chrome −
Click the Chrome menu at the top right-hand corner of your browser.
Select the Settings option.
Click on the Privacy and Security tab from the left sidebar.
Click Show advanced settings at the end of the page.
Next, click on the Site Settings tab.
Now, scroll to the bottom of the page, and find the content section. Click on the JavaScript tab in the content section.
Here, you can select a radio button to turn JavaScript on or off.
Also, you can add the URLS of the custom website to block and unblock JavaScript on particular websites.
JavaScript in Microsoft Edge
Here are simple steps to turn on or turn off JavaScript in your Microsoft Edge −
Click Edge menu (three dots) at top right-hand corner of the edge browser.
Follow More Tools → Internet Options from the menu.
Select Security tab from the dialog box.
Click the Custom Level button.
Scroll down till you find Scripting option.
Select Enable radio button under Active scripting.
Finally click OK and come out.
To disable JavaScript support in your Microsoft Edge, you need to select Disable radio button under Active scripting.
JavaScript in Firefox
Here are the steps to turn on or turn off JavaScript in Firefox −
Open a new tab → type about: config in the address bar.
Then you will find the warning dialog. Select I’ll be careful, I promise!
Then you will find the list of configure options in the browser.
In the search bar, type javascript.enabled.
There you will find the option to enable or disable javascript by right-clicking on the value of that option → select toggle.
If javascript.enabled is true, it converts to false upon clicking toggle. If javascript is disabled, it gets enabled upon clicking toggle.
JavaScript in Safari
When you install the Safari web browser, JavaScript comes installed by default. If you have disabled it and want to enable it, follow the steps below.
Click on the safari menu from the top-left corner.
Select the preferences in the dropdown menu. It will open a new window.
Open the security tab.
Check the Enable JavaScript checkbox in the ‘web content’ section to enable the javascript. You can disable the JavaScript by unchecking the checkbox.
Now, close the preference window and reload the web page.
JavaScript in Opera
Here are the steps to turn on or turn off JavaScript in Opera −
Follow Tools → Preferences from the menu.
Select the Advanced option from the dialog box.
Select Content from the listed items.
Select Enable JavaScript checkbox.
Finally, click OK and come out.
To disable JavaScript support in your Opera, you should not select the enable JavaScript checkbox.
JavaScript in Brave
The Brave is well-known for its security and privacy. So, It doesn’t allow us to disable the JavaScript permanently, but we can disable the JavaScript for the particular website by following the below steps.
Open the website URL to disable the browser for it.
Now, Click on the ‘Brave Shields’ icon in the address bar.
Find the Scripts option in the Shields panel.
The default value of the Scripts is “Allow Scripts”. If you want to disable JavaScript, choose the "Block Scripts" option.
Warning for Non-JavaScript Browsers
If you have to do something important using JavaScript, then you can display a warning message to the user using <noscript> tags.
You can add a noscript block immediately after the script block as follows −
<html> <head> <script> document.write("Hello World!") </script> <noscript> Sorry...JavaScript is needed to go ahead. </noscript> </head> <body> </body> </html>
Now, if the user's browser does not support JavaScript or JavaScript is not enabled, then the message from </noscript> will be displayed on the screen.