Microformats are markup that allow expression of semantics in an HTML (or XHTML) web page. Programs can extract meaning from a standard web page that is marked up with microformats.

Existing XHTML (and HTML) standards allow for semantics to be embedded and encoded within them. This is done using specific HTML attributes:

• class
• rel
• rev

Adding microformats to a standard HTML web page allows machines to process HTML text and to possibly load data into remote databases. This would allow programs such as web crawlers to find items such as contact information, events, and reviews on web pages.

Loosely coupled semantics

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One of the advantages of semantic HTML and microformats (as opposed to XML-based semantics) is that semantic information can be loosely coupled. For example, consider the hCard contact information microformat:

<span class="vcard"> <span class="fn">Joe Blow</span> <span class="org">The Example Company</span> <span class="tel">604-555-1234</span> <a class="url" href="http://example.com/">http://example.com/</a> </span>

If one wanted to make this more aesthetically pleasing, say for an HTML e-mail signature, one could equally encode this as follows (while still retaining all the same semantics):

<pre class="vcard"> __________________ | | <span class="fn">Joe Blow</span> | <span class="tel">604-555-1234</span> |______________________________________________ <span class="org">The Example Company</span> <a class="url" href="http://example.com">http://example.com/</a> </pre>

Which would get rendered as:

__________________ | | Joe Blow | 604-555-1234 |______________________________________________ The Example Company http://example.com/

Specific Microformats

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Several microformats have been developed to enable semantic markup of particular types of information.

• hCalendar - for events
• hCard - for contact information
• hReview(spec) - for reviews
• rel-directory(spec)- for distributed directory creation and inclusion
• rel-nofollow, an attempt to discourage 3rd party content spam (e.g. comment spam).
• rel-tag(spec) - for decentralized tagging (Folksonomy)
• xFolk(spec) - for tagged links
• XFN - for social relationships
• XOXO - for lists and outlines

See also

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• GRDDL
• HTML
• intelligent agents
• RDFa RDF with attributes
• S5 file format
• Semantic Web
• Simple HTML Ontology Extensions (early semantic extensions to HTML done by University of Maryland, College Park)
• web crawlers
• XHTML
• XML

External links

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• microformats.org
  • microformats wiki
• xFolk: An xhtml microformat for folksonomy
• Microformats explained and their effect on Search Engine Optimization
• Embeddable RDF
• micromodels

Knowledge representation | XML-based standards | Semantic HTML

Mikroformat | Microformatos | Microformats | Mikroformāti