Web of Hypertext (RDFa, Microformats) and Web of Data
Dieter Fensel and Tobias Bürger
©www.sti-innsbruck.at Copyright 2009 STI INNSBRUCK www.sti-innsbruck.at Where are we?
# Title 1 Introduction
2 Semantic Web Architecture
3 RDF and RDFs
4 Web of hypertext (RDFa, Microformats) and Web of data
5 Semantic Annotations
6 Repositories and SPARQL
7 OWL
8 RIF
9 Web-scale reasoning
10 Social Semantic Web
11 Ontologies and the Semantic Web
12 SWS
13 Tools
14 Applications
15 Exam
www.sti-innsbruck.at 2 Agenda
1. Motivation: From hypertext to the Web of Data 2. Technical solution, illustrations, and extensions: “Building” the Web of Data 1. Embedding structured information in Web pages • Technical solution – Standards: Microformats, RDFa, GRDDL • Example: Yahoo SearchMonkey “Feeding the monkey with RDFa and Microformats” 2. Linked Data • Technical solution – Principles – Publishing and consuming Linked Data – Adding legacy data to the Web of Data • Examples • Extensions and current developments 3. Summary 4. References
www.sti-innsbruck.at 3 MOTIVATION
www.sti-innsbruck.at 4 Evolution of the Web
Web of Data Semantic Web
Picture from [2] ? Web Social Web (Web 2.0) Hypermedia
Hypertext
“As We May Think”
Picture from [1]
www.sti-innsbruck.at 5 Motivation: From a Web of Documents to a Web of Data
• Web of Documents • Web of Data
Typed Links
Hyperlinks
“Documents” “Things”
www.sti-innsbruck.at 6 Vision of the Web of Data
• Many common things are • The Web of Data is envisioned as represented in multiple data sets a global database • Linking identifiers links these data – consisting of objects and their sets descriptions – in which objects are linked with each other – with a high degree of object structure – with explicit semantics for links and content – which is designed for humans and machines
Content on this slide by Chris Bizer, Tom Heath and Tim Berners-Lee www.sti-innsbruck.at 7 TECHNICAL SOLUTION: PUBLISHING STRUCTURED DATA ON THE WEB
www.sti-innsbruck.at 8 How to “Build” the Web of Data?
• Publish structured data by
– using Web (2.0) APIs [4] – embedding structured information (Microformats, RDFa, GRDDL) – linking data [5]
[6]
[7]
[3]
www.sti-innsbruck.at 9 Microformats
Recommended literature: [5], [8]
www.sti-innsbruck.at 10 What are Microformats?
• “Designed for humans first and machines second, microformats are a set of simple, open data formats built upon existing and widely adopted standards. Instead of throwing away what works today, microformats intend to solve simpler problems first by adapting to current behaviours and usage patterns (e.g. XHTML, blogging).” [5]
www.sti-innsbruck.at 11 What are Microformats? /2
• Are highly correlated with semantic (X)HTML / “Real world semantics” / “Lowercase Semantic Web” [9]. • A way to combine human with machine-readable information. • Provide means to embed structured data in HTML pages. • Build upon existing standards. • Solve a single, specific problem (e.g. representation of geographical information, calendaring information, etc.). • Provide an “API” for your website. • Build on existing (X)HTML and reuse existing elements. • Work in current browsers. • Follow the DRY principle (“Don’t Repeat Yourself”). • Compatible with the idea of the Web as a single information space.
www.sti-innsbruck.at 12 Microformats Illustrated
Content on this slide by Chris Grie