Part Twelve of the CSS 101 - A Beginner's Guide to CSS series is now available. It is titled "Borders in CSS" and, as the title dictates, explains how to create borders with CSS. There are examples of the various border styles, information regarding which units of measurement and colour values to use, and demonstration of common usages of borders in CSS.
I have also created a CSS Reference section, which provides a quick view for CSS poperties and (X)HTML tags. If you want to know more about a certain CSS property or (X)HTML tag, just click the corresponding link and useage information will be displayed. More tags and CSS properties will be displayed over time.
Lastly, I've been asked a few times why I title my HTML code examples "(X)HTML Code" and not just "HTML Code". This is because the examples contain tags included in both XHTML and HTML. Given some people prefer XHTML and others HTML, it makes sense to title the examples in a manner that makes both parties happy. There's no discrimination here!