The purpose of resolving language ambiguities is to help ensure, for example, that a shopper who does a search using a phrase like "used red cars" will also get results from Web sites that use slightly different terms with similar meanings, such as "pre-owned" instead of "used" and "automobile" instead of "car."

For more information about semantic technologies, including search, see Part 1 of this story, "." It explores the technology's potential uses and paybacks, illustrated with real business cases, including ones involving . It also provides some best practices and tips from the trenches for anyone planning, or at least considering, a deployment.

W3C standards are designed to resolve inconsistencies in the way various organizations organize, describe, present and structure information, and thereby pave the way for cross-domain semantic querying and federated search.

To illustrate the advantage of using such standards, Michael Lang, CEO of Revelytix, a Sparks, Md.-based maker of ontology-management tools, offers the following scenario: If 200 online consumer electronics retailers used semantic Web standards such as RDF to develop ontologies that describe their product catalogs, Revelytix's software could make that information accessible via a SPARQL query point. Then, says Lang, online shoppers could use W3C-compliant tools to search for products across those sites, using queries such as: "Show all flat-screen TVs that are 42-52 inches, and rank the results by price."

Search engines and some third-party Web shopping sites offer product comparisons, but those comparisons tend to be limited in terms of the range of attributes covered by a given search. Moreover, shoppers will often find that the data provided by third-party shopping sources is out of date or otherwise incorrect or misleading -- it may not, for example, have accurate information about the availability of a particular size or color. Standards-based querying across the merchants' own Web sites would enable shoppers to compare richer, more up-to-date information provided by the merchants themselves.