jQuery
Classic DOM and AJAX made simple
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read 8 chapters Framework
Created
2006 by John Resig
Language
JavaScript
Size
~30 KB minified
Motto
Write less, do more
Browser support
IE6+ to modern
Still used on
~70% of top websites
Replaced by
Vanilla JS, React, Vue
Best for
Maintaining legacy sites
What is jQuery?
jQuery is a fast, small JavaScript library that simplifies DOM manipulation, event handling, AJAX, and animation. Created by John Resig in 2006, it was the most widely used JavaScript library for over a decade.
Why learn jQuery?
While modern frameworks have replaced jQuery for new projects, jQuery still runs on millions of existing websites. If you maintain WordPress sites, enterprise applications, or legacy codebases, jQuery knowledge is essential.
| Use case | jQuery | Vanilla JS | React/Vue |
|---|---|---|---|
| Existing jQuery codebase | ✅ Essential | ❌ Rewrite needed | ❌ Rewrite needed |
| Simple DOM manipulation | Overkill | ✅ Fine | Overkill |
| New projects | ❌ | ✅ | ✅ |
| WordPress themes | ✅ Common | ✅ | Rare |
What you'll learn
| Chapter | What you'll know |
|---|---|
| Selectors | Find any element in the DOM |
| Events | Click, hover, submit, keyboard |
| DOM | Add, remove, modify content |
| AJAX | Fetch data without page reload |
Start with selectors to learn how jQuery finds elements.