A registry is a shared resource, often available in the form of a web-based service that facilitates dynamic business-to-business interactions. The registry is a key component in Web services architecture, since it allows organizations to publish, discover, and utilize Web services.
It is important to distinguish between a registry (such as UDDI or the ebXML Registry) and a directory. A registry provides capabilities that take advantage of Web services standards. A registry requires an elaborate information model and rich metadata and query capabilities in order to support more complex queries and therefore make the search for Web services as accurate as possible.