Beginning jQuery is your step-by-step guide to learning the jQuery library. jQuery is the most popular JavaScript library in the web developer’s toolkit. Jack Franklin takes you from the basics of getting you started with jQuery, right through to extending jQuery by writing your own plug-ins. You'll discover best practices you can follow, how you can avoid common mistakes, and you'll learn about so many of the things that jQuery has to offer, including how you can: Use jQuery’s powerful tools to dynamically update content on your site, including DOM manipulation. Extend jQuery’s capabilities by writing your own plugins on top of.