New site - XHTML 1 Strict or HTML 5

Question

I'm beginning a very large project in the coming weeks and am trying to decide if I should take the leap into HTML5 land or stick with my time trusted XHTML 1 strict.

The site will be huge. Thousands of pages, video, custom CMS system, lots of social media integration, etc. I'm trying to justify using the new technology, but am unsure (as I've never done a huge site in 5) if everything will go according to plan on older browsers.

I can sit there and talk all day long about the new technology that html5 brings, but when you're sitting in a board room full of execs and the site doesn't work on their IE6 machines...not good.

Let me know what you guys would do. - Thanks

Answer 1

While HTML5 is not fully complete, much of it can be used today. It was designed with compatibility in mind, so a number of the new elements will work in older browsers, even if they don't specifically support HTML5.

You can start using the new doctype - any browser will recognize it as valid. From there, you can do your layouts using the new semantic structural elements - section, aside, header, footer, etc. You'll need to style these a bit to get them appearing correctly, and there is a shiv script for IE compatibility. It takes a little work, but they provide much more semantic value than the generic div.

audio and video elements have fallback capabilities for older browsers, so by all means use them.

Various new form elements and attributes are not widely supported yet, so you probably won't get much value from them right now. Though I quite look forward to using them, as they will reduce need for client-side scripting a fair bit.

IE6 is the obvious element in the room, but with the right setup, and use of fallbacks in HTML5, there should be no serious issues from using HTML5. CSS is another matter, of course. But IE9 is looking rather good, and will help to raise the bar for standards support.

Answer 2

Choosing to use the HTML5 vocabulary is an orthogonal issue to whether to use XHTML syntax. If you want to use HTML5 elements and still work with XML production tools, you can always use XHTML5.

HTML5 is not yet finished so to some extent you will be labelling your documents with a doctype of unknown quantity, and validating it isn't as easy. But if your project is going to be using elements like <video> at any point, using an HTML5 doctype makes sense. (Though hopefully if you are using a custom CMS it should be relatively straightforward to adjust the doctype it spits out in the future anyway?)

None of this is relevant to IE6 compatibility as such. IE6-8 will render the page the same with any of the Standards Mode doctypes, and won't ever render <video> regardless of whether you're using an HTML5 doctype. You will certainly need fallback for any HTML5 extensions you use, such as Flash for <video>. The extended HTML5 semantic elements like <section> or <article>, you don't really get anything for using anyway; avoid them for now.

Answer 3

HTML5 is a better choice here. It offers improvements as well as compatibility; and will render in all browsers. Modern features such as <video> can be sniffed for and replaced by FLV players or other alternative in non-compatible browsers.

XHTML has been redundant since its creation, and XHTML 1.0 (when sent with the correct mime type) doesn't work at all in IE6. Using HTML5, it will both render and be functional, assuming you handle the lack of support of modern features properly.