Microformats are little bits of markup you can add to HTML to let search engines and other technology know what the text represents. This can allow systems to understand a little of the social graph expressed in the connections (links) between pages.

Microformats (μF) are a set of defined HTML classes created to serve as consistent and descriptive metadata about an element, designating it as representing a certain type of data (such as contact information, geographic coordinates, events, blog posts, products, recipes, etc.). They allow software to process the information reliably by having set classes refer to a specific type of data rather than being arbitrary. Microformats emerged around 2005 and were predominantly designed for use by search engines, web syndication and aggregators such as RSS.

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