phpguru.org — HTML4 has been with us for a while now, roughly ten years. And it hasn't really seen a major update. Sure there's XHTML, but that did little more than make things slightly stricter - making you write better quality code if you were at all concerned with compliance. HTML5 does more than that. For one thing it adds a few new features. Not a huge amount, but the ones that it does add are very useful.
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