The World Wide Web Consortium completed an important link between Semantic Web and microformats communities. With 'Gleaning Resource Descriptions from Dialects of Languages', or GRDDL (pronounced "griddle"), software can automatically extract information from structured Web pages to make it part of the Semantic Web. Those accustomed to expressing structured data with microformats in XHTML can thus increase the value of their existing data by porting it to the Semantic Web, at very low cost.
"Sometimes one line of code can make a world of difference," said Tim Berners-Lee, W3C Director. "Just as stylesheets make Web pages more readable to people, GRDDL makes Web pages, microformat tags, XML documents, and data more readable to Semantic Web applications, opening more data to new possibilities and creative reuse."
One aspect of recent developments some people call 'Web 2.0' involves applications based on combining - in 'mashups' - various types of data that are spread all around on the Web. A number of active communities innovating on the Web are sharing data such as calendar information, contact information, etc. These communities have developed diverse social practices and technologies that satisfy their particular needs. For instance, search engines have had great success using statistical methods while people who share photos have found it useful to tag their photos manually with short text labels. Much of this work can be captured via "microformats". Microformats refer to sets of simple, open data formats built upon existing and widely adopted standards, including HTML, CSS and XML.
GRDDL is the bridge for turning data expressed in an XML format (such as XHTML) into Semantic Web data. With GRDDL, authors transform the data they wish to share into a format that can be used and transformed again for more rigorous applications.
The Working group has produced GRDDL use sases that provide insight into why this is useful through a number of real-world scenarios, including scheduling a meeting, comparing information from various retailers before making a purchase, and extracting information from wikis to facilitate e-learning. Once data is part of the Semantic Web, it can be merged with other data (for example, from a relational database, similarly exposed to the Semantic Web) for queries, inferences, and conversion to other formats. The Working Group has also produced a GRDDL service that allows users to input a GRDDL'd file and extract the important data.
Links:
http://www.w3.org/TR/2007/REC-grddl-20070911/
http://www.w3.org/TR/grddl-scenarios/
http://www.w3.org/2007/08/grddl/
