Is HTML/XHTML validation important?

thTeong WebLog|Blog About Everything asks whether validation is important.

Here's my take on the issue: it's very important.

Why is HTML/XHTML validation important?

If your content does not validate, your RSS feeds might be broken as well. Most feed readers will barf when fed broken XML/XHTML. That means fewer readers.

Validation is also important in another sense: when you focus on validation, you inevitably end up doing somethign about semantics in your markup. Everyone benefits from this, especially you, the author, because Google and other search engines benefit from semantic markup.

Plus, broken HTML/XHTML may render in unpredictable ways with different browsers. XHTML-based blogs may not even render under certain circumstances (we're talking about the famous application/xml+html content type here). I don't suppose you'd want to harm your readers' reading experiences, do you?

To help you in your thankless task of ensuring that your WordPress blog always remains valid HTML/XHTML, I've written a special plug-in for it: the WordPress XHTML validator. Download it today!

By the way, thanks for the reference link, thTeong!