Prototyping in XHTML

So what does it mean to prototype with XHTML?

Essentially, it’s the process of using the XHTML itself, and related technologies, to evolve and define your design solution.

And what does an XHTML prototype look like?

While, as we’ll see, that depends on where you are in your prototyping process, an XHTML prototype generally looks like any other web page built with XHTML, with some links or features perhaps being non-functional.

In other words, anything you can build with XHTML, from consumer websites to enterprise applications, you can also prototype with XHTML. As we’ll see, there are numerous advantages to this approach compared to designing with wireframes or other prototyping tools.

Here's a nice article by Anders on same and talks about the same in detail.

Article Link: Prtotyping in XHTML

Source: Boxesandarrows.com