Browser support is critical for any aspect of HTML5 — or any other web technology, for that matter. This appendix is a snapshot of the current state-of-the-art regarding the various new features of HTML5 and CSS3. Each section lists a feature and what version of the five major browsers — Internet Explorer, Firefox, Safari, Opera, and Google Chrome — support that feature, if any.
As a web designer who often pushes the limits, I feel it's necessary for me to accompany this appendix with a caveat. As always when you're deciding whether or not to include a tag or attribute in your code, it's not enough to see that it is supported on one or more browsers. The key is to make sure that the supporting browsers make up the vast majority of the visitors to the site you're building. It doesn't matter if the latest bleeding-edge feature is available in WhizBang 3.1, if hardly anyone who visits your site has that browser.
As of this writing, the final version of Internet Explorer 9.0 has not been released, but it is in beta testing. The following charts include Internet Explorer 9.0 support if it is included in the beta version or has been announced by Microsoft that the feature is expected to be supported. It is entirely possible that some announced or even beta-based features may not make it to the released version.
As this book attests, HTML5 is overflowing with new tags and attributes that bring greatly enhanced functionality. Overall, ...