HTML microformats on O'Reilly's XML.com.
"Microformats are a way to embed specific semantic data into the HTML that we use today. One of the first questions an XML guru might ask is "Why use HTML when XML lets you create the same semantics?" I won't go into all the reasons XML might be a better or worse choice for encoding data or why microformats have chosen to use HTML as their encoding base. This article will focus more on how to extract microformats data from the HTML, how the basic parsing rules work, and how they differ from XML.
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