JavaScript is a popular scripting language that simplifies HTML document traversing, event handling, animating, and Ajax interactions. It was designed to change the way developers write JavaScript code. jQuery is a new and fast JavaScript library that uses JavaScript to simplify tasks like HTML document navigation, event handling, animating, and interacting with Ajax. Documentation on jQuery can be found on sites like api.jquery.com and resources for learning jQuery include learningjquery.com and ajaxian.com.