XML is a Meta Markup Language Not like html troff, latex Make up the tags you need as you need them The tags you create can be documented in a Document Type Definition(DTD) A meta syntax for domain-specific markup languages like MusicML. MathML and Xhtml Languages for Semantic Web
Languages for Semantic Web 11 XML is a Meta Markup Language • Not like HTML, troff, LaTeX • Make up the tags you need as you need them • The tags you create can be documented in a Document Type Definition (DTD) • A meta syntax for domain-specific markup languages like MusicML, MathML, and XHTML
XML Applications A specific markup language that uses the XML meta syntax is called an XML application Different XML applications have their own more constricted syntaxes and vocabularies within the broader XML syntax Further syntax can be layered on top of this; e.g. data typing through schemas Languages for Semantic Web
Languages for Semantic Web 12 XML Applications • A specific markup language that uses the XML metasyntax is called an XML application • Different XML applications have their own more constricted syntaxes and vocabularies within the broader XML syntax • Further syntax can be layered on top of this; e.g. data typing through schemas
XML describes structure and semantics not formatting XML documents form a tree Document Object Model (DOM) Element and attribute names reflect the kind of the element DTD Schema Formatting can be added with a style sheet Cascading Style Sheets(CSS) Extensible Stylesheet language(XSL) Languages for Semantic Web
Languages for Semantic Web 13 XML describes structure and semantics, not formatting • XML documents form a tree – Document Object Model (DOM) • Element and attribute names reflect the kind of the element – DTD, Schema • Formatting can be added with a style sheet – Cascading Style Sheets (CSS) – Extensible Stylesheet language (XSL)
XML Hypertext A Uniform Resource Identifier(URI) names or locates a resource An XLink defines connections between two or more documents identified by urls XPath identifies particular nodes within a document An xPointer adds an xpath to a uri XBase defines the URi against which relative Urls are resolved XInclude embeds a document identified by a uri inside an XML document Languages for Semantic Web
Languages for Semantic Web 14 XML Hypertext • A Uniform Resource Identifier (URI) names or locates a resource • An XLink defines connections between two or more documents identified by URIs • XPath identifies particular nodes within a document • An XPointer adds an XPath to a URI • XBase defines the URI against which relative URIs are resolved • XInclude embeds a document identified by a URI inside an XML document
A Song Description in HTML <dt>Hot Cop <dd> by Jacques Morali, Henri Belolo, and Victor Willis <u1> <li>Producer: Jacques Morali <li>Publisher: PolyGram Records <li>Length: 6: 20 <li>Written: 1978 <li>Artist: Village People </u1> Languages for Semantic Web
Languages for Semantic Web 15 A Song Description in HTML <dt>Hot Cop <dd> by Jacques Morali, Henri Belolo, and Victor Willis <ul> <li>Producer: Jacques Morali <li>Publisher: PolyGram Records <li>Length: 6:20 <li>Written: 1978 <li>Artist: Village People </ul>