A design team at Charteris plc has developed a 'Meaning Definition Language' (MDL) as a "bridge between XML structure and meaning, expressed precisely in XML. MDL defines how the structures of an XML document (elements, attributes and XPaths) convey meanings (about objects, properties and associations). The purpose of the Meaning Definition Language (MDL) is thus to define what XML documents mean and how they express that meaning. MDL defines what a document can mean in terms of a UML class model or RDF Schema, and defines how to extract the meaning, in terms of XPath. MDL is a simple language with many applications, such as: (1) validating that an XML language can convey its intended meaning, (2) automated translation of documents between XML languages, (3) automated retrieval of information on the Semantic Web, (4) supporting meaning-level XML query languages, and (5) programming APIs to XML at the level of meaning, independent of document structure. MDL will enable tools and users to interface to XML at the level of meaning rather than structure. MDL-based automated XML translation and a meaning-level query language are already supported."