Microformats are open data formats that some Yahoo! sites support. You can't see them (unless you do a "view source" on a web page), but they're there -- bits of HTML that describe things like contact information (hcard), a review (hreview), an event (hcalendar), or a listing (hlisting). Microformats make data in web pages reuseable since the data is in a standard, canonical, format instead of just a jumble of HTML. Thousands of sites expose their data in Microformats, and that data is available for developers to use. One of the best opportunities for developers to make use of Microformats is in the forthcoming Firefox 3 web browser which features a new global Microformats object and API. The new API makes finding and parsing Microformats trivial and efficient. Although Firefox 3 is still in beta, you can download the latest version here to start working on extensions.
Yahoo's Kelkoo online shopping site is the latest Yahoo! site to use Microformats. Kelkoo uses the hlisting Microformat to expose product information. Kelkoo Product Manager Nicolas Leroy imagines three efficiencies from widespread use of the hlisting Microformat in his blog post:
* Auto-discovery of offers on merchant websites is made trivial by the adoption of hlisting by merchants. Comparison engines can rely on easier and more reliable crawler technologies to retrieve offers.....merchants could even stop pushing feeds to comparison engines -- only a list of URLs or just their domain name might be needed.
* Social shopping: bookmarking of listings is now trivial as structured data can be easily extracted from browsed pages -- no more complex bookmarking tools that ask the end user to identify the product name, the image, etc.
* We can imagine a browser extension (like the Operator plugin for Firefox) that lets users bookmark offers from various sites and call comparison engines to compare prices for similar offers.
If you want to see Microformats in web pages you browse, you can install the Tails Export or Operator Firefox extensions which work in your Firefox 2 web browser. Then you can see the hcalendar, hreview, and hcard support in Yahoo! Local, the hcard support in Flickr, the hcalendar and hcard support in Upcoming.org, the hlisting support on Kelkoo, and the hreview support on Yahoo! Tech. You may also notice other Microformats popping up such as rel-tag and XFN. Look for more Microformats to appear on Yahoo! sites in 2008.