The history of HTML

The three versions of HTML: Strict, Transitional, and Frameset

Introduction to XHTML and its stricter syntax requirements

Using Document Type (DOCTYPE) Declarations

Standards vs. Quirks mode in browsers

Validating your markup

Indicating a document’s character encoding

I’m going to warn you right now... this is a big, geeky chapter full of some pretty dry material. But I know you can handle it. If you have any notion of doing web development professionally, you’ll be required to know it. Even if you don’t, it’s important stuff.

Professional web designers know that the best way to ensure consistency and accessibility across multiple browsers and devices is to write standards compliant web documents. Standards compliance simply means that your documents abide by all of the rules in the latest Recommendations published by the World Wide Web Consortium (the W3C). That includes HTML and XHTML for markup, but also other standards for style sheets (CSS) and accessibility.

This chapter covers what it takes to get compliant. It gets into the nitty-gritty on HTML and XHTML and their various versions. It begins with a fair amount of story-telling, painting the picture of (X)HTML’s past, present, and future. Once you have a feel for the big picture, the markup requirements that follow will make a lot more sense. So sit back and enjoy the tale of HTML and XHTML. (If you’re thinking, “C’mon! I don’t have time for this... ...

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