jQuery is a fast and concise JavaScript library that simplifies HTML document traversal, event handling, and animation. Developers use it to write less code while accomplishing more. By learning it, you can rapidly enhance web interactivity and handle cross-browser inconsistencies with ease.

To excel in jQuery, consider mastering the following concepts:

1. Selectors and Traversal: Understand how to select and manipulate specific HTML elements efficiently.
2. Event Handling: Learn to respond to user interactions, like clicks or keypresses, using event methods.
3. Effects and Animations: Grasp the methods to show, hide, slide, or animate elements smoothly.
4. AJAX with jQuery: Master making asynchronous requests to load data or update parts of a page without a full refresh.
5. Plugins and Extensions: Familiarize yourself with using existing plugins and creating your own to extend jQuery’s capabilities.