Chapter 1. Getting Acquainted with JavaScript

For Web site creators, the evolution of HTML has been a mixed blessing. In the early days of the World Wide Web, HTML was fairly simple, and it was easy to learn most everything you needed to learn about putting together Web pages.

As the Web grew, page designers' aspirations grew as well, and their demand for greater control over the look of the page forced HTML to change and become more complex.

Because the Web is a dynamic medium, page designers also wanted their pages to interact with the user, and it soon became obvious that HTML was insufficient to handle the demand. Netscape invented JavaScript as a way to control the browser and add pizzazz and interactivity to Web pages.

Since its creation, JavaScript has evolved quite a bit (although occasionally in different directions, depending on the browser). Later in this book, we'll discuss JavaScript's evolution in detail.

In this chapter, you'll learn what JavaScript is (and what it isn't); what it can do (and what it can't); and some of the basics of the JavaScript language; and you'll get an introduction to Ajax, the exciting combination of JavaScript and other technologies that is enabling the next wave of interactivity and creativity for Web sites.