Top jQuery Interview Questions and Answers (2024)

With the motto “write less, do more,” jQuery is one of the most used JavaScript libraries for web development. It is open-source and used on millions of websites. jQuery makes working with JavaScript on a website much easier and is cross-browser compatible.

With the changing web development landscape with modern frameworks and libraries like ReactJS, AngularJS, and VueJS gaining popularity, jQuery remains valuable. 

Read on to learn more about jQuery with some of the most commonly asked jQuery Interview questions and answers curated by industry experts. This article is designed for both beginners and professionals who want to prepare for jQuery Interviews.

1. What is jQuery?

• JQuery is one of the most popular Javascript Library
• JQuery is fast, lightweight, "write-less, do more" Javascript Library
• Jquery is used to simplify HTML DOM Tree traversal and manipulation, CSS Manipulation, HTML event methods, AJAX, Utilities, Effects and animations

2. Is jQuery a server-side scripting or client-side scripting?

JQuery is client-side scripting.

3. What is the difference between Javascript and JQuery?

• jQuery simplifies the use of javascript Language
• Javascript is an Interpreted Programming language. whereas JQuery is a built-in library built for JavaScript.

4. Is jQuery a programming language?

No, JQuery is a well-written Javascript Framework and not a programming Language

5. What are the common uses of JQuery?

JQuery helps to

• Simplify common JavaScript tasks
• JQuery helps to modify the appearance of a web page
• Access elements in a document
• Alter the content of a document
• Animate changes being made to a document
• Retrieve information from a server without refreshing a page

6. What are the common features of the JQuery Library?

• HTML/DOM manipulation
• HTML event methods
• Effects and animations
• CSS manipulation
• AJAX
• Utilities

7. Is it possible for jQuery to work for XML documents?

jQuery doesn't work for XML documents; it only works for HTML documents.

8. Is jQuery Library built for Server-side scripting or client-side scripting?

jQuery Library is used for client-side scripting, and jQuery is not compatible with server-side scripting

9. What are the methods used to provide effects in JQuery?

• Show()
• Hide()
• FadeIn()
• FadeOut()
• Toggle()

10. What are the types of Selectors in the jQuery Library?

• Selectors in Jquery are used to find the HTML Elements
• Basic elements are 
  • Name
  • class
  • #ID
  • Attribute
  • Universal

11. What is the difference between an ID Selector and a Class selector in JQuery?

• ID selector and class selector are used to find HTML Elements
• Like in CSS, the ID Selector and class selector are the same
• You can use the ID selector to select only one element. Here, the Class selector is used to select a group of elements

12. How do you select an Item using ID?

This code selects 0 or 1 elements depending on whether the specified ID exists.

    $( "#myDivIdName" );

13. How do you select an Item using Class?

This code selects any number of elements using the same class. Any number of elements can have the same class

    $( ".myClassName" );

14. Which are the fastest selectors in JQuery?

    id and element

15. What are the events in JQuery?

An event represents a moment when something happens.

Examples:

• Selecting the radio button
• Selecting an element
• Moving the mouse over the element
• Mouse events: click, dblclick, mouseenter, mouseleave.  
• Keyboard Events: keyup, keydown, keypress.
• Document or Window Events: unload, scroll, load, resize.
• Form Events: submit, focus, change, blur.

16. Is it possible to test whether an element exists using JQuery?

Yes. It is checked by using the .length property of the jQuery collection.

17. How do you disable a form ELement using jQuery?

You can disable a form element using the .prop() method.

To disable #myDiv, use the following code

    $( "#myDiv" ).prop( "disabled", true );

18. What is the difference between onload() and document.ready() methods?

The onload() method is used to load the HTML code. Whereas document.ready() method is pure javascript method and is used to render Javascript code that is needs to display the page.

19. What are the popular JQuery CDNs?

There are 3 Popular CDNs.

• jQuery
• Google 
• Microsoft

19. What are the different methods of making Ajax requests in jQuery?

You can make Ajax calls using the following jQuery Methods,

• load()
• $.getJSON()
• $.getScript()
• $.get()
• $.post()
• $.ajax()

20. What is the difference between jQuery UI and Jquery?

jQuery UI is built on top of the jQuery javascript library and can be used to build interactive web applications. If you use jQueryUI, you also have to include jQuery. jQueryUI is on the top of jQuery.