I wanted to write an article on why every web site should use web standards and what web standards are used for when I came across an amazing article by Paul Boag, the owner of Boagworld.com. His article, titled "A better way to build your website," explains in detail why web standards are needed and how they can benefit your website. I love this article and also found his podcast on web accessibility to be very informative. He did such a great job that I don't feel writing an entire article about web standards would do anything but reiterate what he said. If you haven't already, I strongly suggest you take a look at his article and consider switching to a web standards based website.
Update: More great links explaining why you should use web standards.