There are several browsers for viewing the web. IE8, FX, Chrome, Safari, and IE6. In addition there are proprietary browsers on smartphone. All these browser have to interpret the same webpages but not infringe on software copyrights owned by the others. So the browsers do not all work the same. There is a big program challenge to make websites look the same in browsers that do not work the same.

HTML4 and basic HTML are for the most part identical. HTML4 simply adds a few more functions. The proposals for HTML5 are a radical departure from HTML4 and will present radical programming challenges for backward compatibility whenever the final version of HTML5 is adopted.

CSS3 is still in a development phase, but many aspects of CSS3 have been adopted in the latest browser software versions. I would direct you attention to StLouisKidsBirthdayParties.com for examples of CSS3. Open it is the various browsers and see the differences. IE8 does not support the rounded boxes, FX did not accept all fonts, and Chrome and Safari did accept all changes.

The Logo with citys and phones was a png image, the background a tiled repeated image, the vertical colors on the page were a repeated image, and the video a swf operated by java. Otherwise, all shadows, lines, boxes, curves, colors, etc were generated by CSS3 on simple HTML coding.