2. JavaScript and the Document Object Model

Back to the Basics

The most important technology in a Web designer's toolkit is HTML. Without a markup language, you can't give the content any structure. Once the markup structure is in place, it can be enhanced with other technologies, such as CSS and JavaScript.

This chapter will serve as a crash course in JavaScript, a technology that is essential for Ajax. If you are already well-versed in JavaScript, you can skip this chapter although you might still appreciate this reminder of syntax and terminology.


Whereas HTML is a markup language, JavaScript is a programming language. Instead of specifying structure, it performs logical operations and calculations.

There are plenty of programming ...

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