Differences between HTML, XHTML and DHTML

I'm familiar with HTML and CSS, having done some website programming myself several years ago. But I'm not well-versed with XHTML and DHTML.

So, please bear with me with this: What are the differences between HTML, XHTML and DHTML?

XHTML is HTML rewritten to follow XML guidelines, so it can work with XML based clients/agents. It's just a slightly differenct syntax, every tag must be closed, tags can't overlap each other...

I don't know anything about DHTML.

Originally Posted by mac What are the differences between HTML, XHTML and DHTML?

HTML

This is a broad umbrella under which other topics shelter. For the purposes of differentiating HTML from XHTML, the former is taken to mean "SGML-based HTML". That is, the traditional HTML that makes up the web.

XHTML

As traditional HTML is SGML-based, XHTML is XML-based. Because an XHTML document is an XML document, it must follow the latter's rules with the most common difference between it and HTML being that all elements must have closing tags (<p>…</p>) or close themselves (<br />). With HTML, closing tags are optional (<p>…. and <br> are fine).

There are a whole heap of other differences, great and small, but they're just a Google search away.

DHTML

Unlike HTML and XHTML, DHTML is not a type of document. It means "Dynamic HTML" and is a term used to encompass the use of a range of technologies ((X)HTML, JavaScript, CSS …) in order to change the page after it has loaded (i.e. changing a static page into a dynamic one). DHTML is quite an old term and is used far less than it once was.

I'd stick with XHTML primarily. There's really no difference, it's just that validation is a lot tougher than HTML (XHTML has more rules), and it forces you to just read cleaner code.

Xhtml is going to be your best bet with any coding. It's going to be cleaner, more organized and better for static sites. Now if you're looking to make your website more dynamic then I would go with php.

Originally Posted by krymson Xhtml is going to be your best bet with any coding. It's going to be cleaner, more organized and better for static sites. Now if you're looking to make your website more dynamic then I would go with php.

How is XHTML going to be cleaner, more organized and better for static sites? It's up to the individual writing the code to make sure it's "clean" (validated?), organized and "better" for static sites.

I can use HTML 4.1 and have it validate under strict compliance and have just as good (if not better) of a site with clean and organized code.

Same can be said for HTML5.

Thanks for the replies folks. I see that Blogger uses XHTML then. I notice the space+"/" at the close of every "br" code. I've studied HTML before to help me with my blogging. The slight variation in the syntax has mystified me but I didn't bother to investigate til now

Now that you're mentioning XML, may I ask what does has to do with the new format of MS Office files? Files now have "x" added to the prefix (docx, xlsx, pptx). I gathered --- but I'm not sure --- that "x" refers to XML.

Originally Posted by mac Now that you're mentioning XML, may I ask what does has to do with the new format of MS Office files? Files now have "x" added to the prefix (docx, xlsx, pptx). I gathered --- but I'm not sure --- that "x" refers to XML.

Yes, it does: http://en.wikipedia.org/wiki/Office_Open_XML

shrikrishnatech, that's some good copy-and-pasting there.