HTML and CSS Reference
A Brief Look
In this chapter, you will learn how to ...
● Describe the purpose of the Document Object
Model and list some common events
tag and the alert() method
● Describe the considerations for XHTML
● Use variables, operators and the, if control
● Create a basic form validation script
If a popup window mysteriously appears while you are
make your Web pages come alive! You can display an alert box containing an
important message for the user. You can display an image when a user moves
the mouse pointer over a link, and much more. You don't have to be a pro-
grammer to be able to add a little sizzle to your Web pages. This chapter intro-
you can build on to create your own Web pages.