HCard

hCard is a microformat for publishing the contact details (which might be no more than the name) of people, companies, organizations, and places, in (X)HTML, Atom, RSS, or arbitrary XML. The hCard microformat does this using a 1:1 representation of vCard (RFC 2426) properties and values, identified using HTML classes and rel attributes.

It allows parsing tools (for example other websites, or Firefox's Operator extension) to extract the details, and display them, using some other websites or mapping tools, index or search them, or to load them into an address-book program.

In May 2009, Google announced that they would be parsing the hCard, hReview and hProduct microformats, and using them to populate search-result pages. In September 2010 Google announced their intention to surface hCard, hReview information in their local search results. In February 2011, Facebook began using hCard to mark up event venues.

Consider the HTML:

With microformat markup, that becomes:

Here the properties fn,org (organization), tel (telephone number) and url (web address) have been identified using specific class names; and the whole thing is wrapped in class="vcard" which indicates that the other classes form an hcard, and are not just coincidentally named. If the hCard is for an organization or venue, the fn and org classes are used on the same element, as in or <span class="fn org">Wembley Stadium</span>. Other, optional, hCard classes also exist.

It is now possible for software, for example browser plug-ins, to extract the information, and transfer it to other applications, such as an address book.

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