jQuery is a fast and concise JavaScript Library created by John Resig in 2006 with a nice motto: Write less, do more. jQuery is designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax. It is free, open-source software using the permissive MIT License. As of May 2019, jQuery is used by 73% of the 10 million most popular websites. Web analysis indicates that it is the most widely deployed JavaScript library by a large margin, having at least 3 to 4 times more usage than any other JavaScript library.jQuery's syntax is designed to make it easier to navigate a document, select DOM elements, create animations, handle events, and develop Ajax applications. jQuery also provides capabilities for developers to create plug-ins on top of the JavaScript library. This enables developers to create abstractions for low-level interaction and animation, advanced effects and high-level, themeable widgets. The modular approach to the jQuery library allows the creation of powerful dynamic web pages and Web applications.

Following are the features of jQuery:

1. Simple and easy:
It have predefined method using you can perform any task easily compare to JavaScript. And it is easy to learn.
2. Lightweight:
It is very lightweight library - about 19KB in size ( Minified and gzipped ).
3. CSS manipulation:
It have predefined css() method for manipulate style for any Html elements.
4. Event handling:
It support event handling like click mouse button.
5. Ajax Support:
It support ajax, you can develop a responsive and feature-rich site using AJAX technology.

List of top 5 best websites for learning JQuery :-

• W3 Schools

  w3schools is doing a remarkable job in providing tutorials on various technologies. You just name the technology and you will find a tutorial related to that on w3schools. The tutorials on JQuery overs every topic and has an online editor as well where you can perform things practically. The tutorial starts with an introduction of JQuery and then digs deep into the technology as we progress further.

  
• CodeAcademy

  Codecademy helps you learn jQuery online so that you can leverage your skills in creating animation and building interactive websites. The estimated course time is 3 hours and more than 500 thousand students have registered for this course. The course perfectly answers your query of “how do I learn to code” by offering online editor with every tutorial which allows you to execute whatever you have learned.

  
• Tutorialspoint

  Tutorials point has been in these business from a long time and explain things in the simplest way possible. The JQuery course is very structured and can be understood even by a beginner. It starts with the basics and covers topic like attributes, CSS, DOM, AJAX etc. and then move towards advanced topics like Interactions, Widgets, Theming, Plugin and Utilities.

  
• Learn.jQuery

  Learn.jQuery is the best place to start learning as it focuses on basics, deals with common problems faced by developer and makes you familiar with the standard practices of JQuery. It covers topic such as JQuery introduction, events, Ajax calls, use of plugins, code organization etc.

  
• CodeSchool

  Codeschool has divided the course into different levels. The course digs deeper as you move to the next level. Each level has challenges associated with it which needs to be accomplished. These challenges are based on the learnings that you have grasped from the video tutorial. The first 5 levels of course are free and covers topic such as traversing DOM, working with DOM, listening to DOM and styling in JQuery.