CSS and HTML

Everything you need to know about HTML5 and video codec support. And a chunk of html code that embeds a video into a website using the HTML5 <video> element, falling back to Flash automatically, without the use of JavaScript or browser-sniffing. It therefore works in RSS readers (no JavaScript), on the iPhone / iPad (don’t support Flash) and on many browser platforms.

If you’ve always found using floats in CSS to be mostly trial and error then this Floatorial might clear up matters a little.