In this chapter, you learned about how Ajax has changed the style of programming in contemporary web applications. You did so by turning off JavaScript in your browser and seeing what happens to Flickr and Google Maps. You studied the functionality of a JavaScript library (Yahoo! UI Library) and Google Maps via the Firebug Firefox extension and the JavaScript Shell. You also learned the basics of invoking the Flickr API in Ajax. Finally, you learned how to create a basic Greasemonkey script that inserts a permanent link into a New York Times online article. Although there is much more to learn concerning JavaScript and Ajax, this chapter provides the necessary background to the following chapters.