Using Microformats to Get Started with the Semantic Web

Web developers use microformats to get out of the Semantic Web starting gate. True technological paradigm shifts don't happen easily. There's always the challenge of getting from here to there. The IT industry has typically referred to this as the "installed base" problem, and it represents as thorny an issue for new development concepts as it does for actual products. This has been one of the issues standing in the way of more rapid enterprise adoption of the Semantic Web. Until relatively recently, early users of Semantic Web technologies and techniques did not have a "bridge" from current to new Web practices that would make the transition easier. Microformats provide such a bridge.

Microformats are a set of standards designed for humans first and machines second that help people and applications share commonly needed information over the Web. One of the most commonly used is the hCalendar microformat, which is used to send email invitations to a meeting or event. Any person reading an email built with the hCalendar microformat can easily comprehend the information in it (date and time of proposed meeting, who is proposing it, the subject of the meeting, etc.); additionally, however, the information can automatically be read by and inserted into an electronic calendar application. "With microformats, people have begun agreeing upon standards they can implement that use Semantic Web technologies to solve problems-but in a way that builds on current ways of doing things, rather than requiring revolutionary changes to behavior," says Scott Abel, CEO of Indianapolis-based The Content Wrangler.

This notion of basing early Semantic Web applications upon existing best practices that modern Web designers have been championing for years is critical to the enormous-and rapid-success of microformats, says Tantek Celik, a senior technologist at Technorati, one of the founders of, and a prominent Semantic Web blogger. "This practice of 'paving the cowpaths' makes microformats implementable by nearly anyone who can write HTML," says Celik.

Making Semantics Available

There are two reasons that people are so excited about microformats, according to experts. First, they are very easy to use and support. Secondly, by enabling Web sites to publish, share, and reuse common information building blocks like contacts and events, they empower users to share and communicate information both more efficiently, and with greater accuracy.

"Indeed, microformats represent some of the first practical uses of the Semantic Web," says Lew Tucker, CTO of Radar Networks, a Semantic Web startup based in San Francisco. "Microformats are a first step toward more universal acceptance of some of its key precepts," says Tucker.

"Many Semantic Web technologies and concepts are too abstract for typical users or even programmers to understand, much less make use of," agrees Celik. "By focusing on today's actual human publishing behaviors and use cases, microformats solve specific common 'data reuse' problems today."

For example, companies are beginning to put contact information on their Web sites into the hCard microformat, which allows browsers to add it to their address books with a single click. Similarly, services such as Yahoo! Local and Google Maps provide HTML enhanced with microformats so that browsers using Firefox 2.0 with the popular "operator" plugin can search for nearby restaurants and add their addresses and phone numbers to address books. Likewise, the popular business networking site LinkedIn uses the hResume format to publish resumes that potential employers can download with one click.

Growing Adoption

Future uses of microformats promise even more benefits. "In additional to quickly sharing and even subscribing to contact information and events listings, microformats have been developed to aggregate, index, and search for information not just on a single site, but across the Web," says Celik.

The potential for enterprises to benefit from microformats is enormous, says Tucker. "With so much different information locked up in so many different databases and formats, there's a real need to find a way to access it more easily and intuitively," he says. Although many companies are putting Web-based front-ends onto these databases, that can actually make the information harder to access. "For example, if you put customer information into HTML, that makes it difficult for someone to copy that information into another application," he says. "But as organizations begin to adopt microformats, that provides for a universal exchange mechanism for the most common types of information across different data sources."

One area in particular that the Semantic Web has been weak in addressing is auto-discovery of semantics, according to an article "Microformats in Context," by Uche Ogbuji, published on the O'Reilly site. According to Ogbuji, the only way to learn the convention of a microformat is by understanding the format specifications. The Gleaning Resource Descriptions from Dialects of Language (GRDDL) initiative attempts to address just that. Among other things, GRDDL provides a "profile," or a "convention for a host language that expresses URIs to assert which microformats are actually used in a document instance," writes Ogbuji. This "binds microformats to resource description format (RDF) models," he writes. Although designed as a metadata model, RDF formats have come to be accepted as a basic method for modeling data.

This ability to get away from siloed data that can be quickly understood by either humans or machines, but not both, is what microformats promises. "And we're beginning to see microformats becoming universally accepted across a broad range of applications," says Tucker. "This bodes well for the Semantic Web in general."