Sean of Elementary Group Standards asked me, as part of a CSS Spring Reboot 2006 ques­tion­naire, why I used HTML 4. Was using HTML instead of xHTML a con­cious choice on my part? Absolutely.

While the other people who were ques­tioned man­aged to keep it nice and con­cise, I man­aged to write up a whole bucket load of words about it. As oth­ers asked me why I made sure Bite Size Standards is HTML 4, I’ve decided to post my answer here too.

As pub­lished on Elementary Group Standards:

“I’ve used xHTML for 5 years, from 2001 til 2006. My ori­ginal reason for using it was that it is sup­posed to be the future. It would have bene­fits like in-line SVG and MathML. It was presen­ted as TheThingToUse™ with CSS.

There are two things about xHTML which make it a poor choice for (pub­lic) sites. Both of them have to do with xHTML’s mime-types. In short, xHTML can be sent with text/html or application/xhtml+xml as the mime-type. On the web xHTML is usu­ally sent as text/html, as Internet Explorer (which has 83+% mar­ket share) doesn’t sup­port the other mime-type. Both mime-types are valid for xHTML 1.0, but (sup­port­ing) browsers do handle them differently.

It’s the hand­ling of the same code dif­fer­ently where xHTML’s prob­lem lies. When xHTML 1.0 is sent as text/html, it is handled as HTML. This means that it has zero user bene­fits over HTML 4.01.

When sent as application/xhtml+xml, you could use MathML — but — the browsers will also apply dra­conian error hand­ling. This way users vis­it­ing the site will be pun­ished (by not being able to see the site) for mis­takes by the cre­ator (which could be the developer, the CMS, the per­son updat­ing the text or indeed the user her/himself just writ­ing some­thing). Simple things like a mis­placed “&” on a page (instead of “&”) will com­pletely shut off a page from its users.

So not only are there no bene­fits over HTML 4.01 because you have to send Internet Explorer text/html — you do get user-punishing error hand­ling from other browsers if you decide to send to them the application/xhtml+xml mimetype.

No bene­fits but increased head­aches? Mwa, count me out.

Some people might say ‘but xHTML is the future!’ This may well be, but is of little con­sequence. The future ver­sions of xHTML (1.1 and 2.0) are not back­wards com­pat­ible with xHTML 1.0, so writ­ing xHTML now gains you little in the future. Furthermore HTML 5 is com­ing. Who says that can’t be the future?

My recom­mend­a­tions for writ­ing HTML? Use the doc­type ‘HTML 4.01 Strict’ and write your code as xHTML com­pat­ible as pos­sible. This means self-closing tags in the body, but not in the head.*

*Little known fact: It’s actu­ally in the spec that you’re not allowed to self-close the meta or link tags. Quite silly in prac­tical terms, and I would sug­gest to the HTML 5 people that they change that¹.

I hope this answers all the ques­tions people have, but if you have any more (or dare to ques­tion my argu­ments!) don’t hes­it­ate to use the com­ment form accom­pa­ny­ing this journal entry.