HTML, XHTML, and CSS All-In-One Desk Reference For Dummies®

Chapter 2. It's All about Validation

In This Chapter

• Introducing the concept of valid pages

• Using a doctype

• Introducing XHTML 1.0 Strict

• Setting the character set

• Meeting the W3C Validator

• Fixing things when they go wrong

• Using HTML Tidy to automatically clean your pages

Web development is currently undergoing an important revolution. As the Web matures and becomes more important, it becomes more important to ensure that Web pages perform properly. There is a new call for Web developers to follow voluntary standards of Web development.

Somebody Stop the HTML Madness!

In the bad old days, the Web was a pretty informal affair. People wrote HTML pages however they wanted. Although this was easy, it led to a lot of problems:

• Browser manufacturers added features that didn't work on all browsers. People wanted prettier Web pages with colors, fonts, and doodads, but there wasn't a standard way to do these things. Every browser had a different set of tags that supported enhanced features. As a developer, you had no real idea if your Web page would work on all the browsers out there. If you wanted to use some neat feature, you had to ensure your users had the right browser.

• The distinction between meaning and layout was blurred. People expected to have some kind of design control of their Web pages, so all kinds of new tags popped up that blurred the distinction between describing and decorating a page.

• A table-based layout was used as a hack. HTML didn't have a good way to handle layout, so clever Web ...