Agenda

• What is the Semantic Web?
• What is RDF?
• What are Microformats?
• RDFa vs. Microformats
• Real world usage
• What to expect?

What is the Semantic Web?

• Dream of W3C-member Tim Berners-Lee
• "The Semantic Web is an extension of the current web in which information is given well-defined meaning, better enabling computers and people to work in cooperation"
  (Tim Berners-Lee)
• Based on standards and markup-languages
• Web-content interpretable by machines
• E.g. XML » XML schema » RDF » RDF schema » OWL

What is RDF?

Resource Description Framework

• Specifications for a metadata model
• Based on triples: subject-predicate-object
• Subject := resource (being described)
• Object := object of the relationship
• Predicate := expresses relationship between subject and object

What is RDF? (cont'd.)

Visible result

What is RDF? (cont'd.)

Visible result

Invisible Overhead

<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns"
         xmlns:dc="http://purl.org/dc/elements/1.1/">
  <rdf:Description
   rdf:about="http://www.myhpi.de/~schapran/pke/">
    "<dc:title>
      Microformats - Designed for humans first...
    </dc:title>"
    by
    <dc:publisher>
      Matthieu-P. Schapranow
    </dc:publisher>
  </rdf:Description>
</rdf:RDF>

What are µFs?

• Revolution started with hReview, early 2004
• Introduced on Supernova 2005, June 20th
• Directly includable in any XHTML compliant document
• Maintainers: Tantek Çelik, Dan Cederholm, Rohit Khare, Ryan King, Kevin Marks

What are µFs? (cont'd.)

What are µFs? - hCard

From vCard...

BEGIN:VCARD
  VERSION:3.0
  N:Schapranow, Matthieu-P.
  FN:Matthieu-P. Schapranow
  URL:http://myhpi.de/~schapran/pke/
  ORG:Hasso-Plattner-Insitute for IT Systems Engineering (HPI)
END:VCARD
		

What are µFs? - hCard (cont'd.)

...to hCard

<div class="vcard">
  <a class="url fn" href="http://www.myhpi.de/~schapran/pke/">
    Matthieu-P. Schapranow
  </a>
  (<span class="org">
    Hasso-Plattner-Insitute for IT-Systems Engineering (HPI)
  </span>)
</div>

What are µFs? - hCard (cont'd.)

• Hardly no overhead to annotate contact information semantically
• Scenarios
  • flickr.com
  • conference speakers announcements
  • browser plugins (Semantic Web Browser), such as tails extensions
  • ...and many more
• But, also a simple way to aggregate confidential data, e.g. by spammers

RDFa vs. µFs

µF example

<a class="email fn"
   href="mailto:spam@hpi.uni-potsdam.de">
     Matthieu-P. Schapranow
</a>

RDFa example

<a rel="email" property="fn"
   href="mailto:spam@hpi.uni-potsdam.de">
     Matthieu-P. Schapranow
</a>

• Equilibrium of content?

RDFa vs. µFs (cont'd.)

µF example

<a class="email fn"
   href="mailto:spam@hpi.uni-potsdam.de">
     Matthieu-P. Schapranow
</a>

RDFa example

<a rel="email" property="fn"
   href="mailto:spam@hpi.uni-potsdam.de">
     Matthieu-P. Schapranow
</a>

• Missing ontology in the µFormats example!

Real world usage

• Browser Extensions (firefox)
  • Tails
  • Greasemonkey scripts for hCard, hCalendar, xFolks, etc.
  • Microformat extension
• Blogging Extensions
  • Structured Blogging for Wordpress

Real world usage - edgeio.com

• Launched February 2006
• Weblog based business as niche for small and large companies
• Works as a RSS aggregator
• Categorized by tags: Housing, Services, For Sale, Jobs, etc.
• Similar example: SimplyHired.com

Real world usage - rubhub.com

• Determines relationships between websites and peoples
• XFN lookup engine created by Phil McCluskey in 2004
• Crawls websites with XFN attributes to identify relationships
  • Reciprocal
  • Incoming
  • Reflexive
• Scenario
  • Find alternative connections for supplies in producer chains
  • Bookseller, Car suppliers, internal contact management within large companies

Real world usage - technorati.com

• Offers semantic search within cumulative web-content of all subscribed users
• Indexes hCard, hCalendar, and hReview
• Cumulative data is updated via event-driven pings
• Underlines interconnections between associative content

Real world usage - technorati.com (cont'd.)

Producer's side

<a rel="tag" href="http://technorati.com/tag/value">value</a>
		

Consumer's side

http://technorati.com/tag/value
		

Latest Improvements

http://kitchen.technorati.com/event/search/Potsdam
http://www.pingerati.net
		

Tradeoffs

• Content absolutely unfiltered
• Cascading effects may result in public access to confidential data

Real world usage - Live-Clipboard

• Directed by Ray Ozzie, CSA & CTO at Microsoft
• DHTML-control allowing copy & paste of website parts using the Live Clipboard XML data format
• Consists of UI element and Clipboard object model
• Serialized XML structure may contain any XML data, e.g. hCalendar and iCalendar simultaneously

Real world usage - Live-Clipboard (cont'd.)

• Live Clipboard demos by Ray Ozzie
  • Blog
  • PC2Web
  • Web2Web
  • WireSite2PC
  • WireSite2Site
• Additional clipboard approach using eRDF
• Scenarios
  • Copy a photo feed, paste it into your Windows Explorer
  • Copy an event from eventful.com, paste it into your Outlook

Real world usage - Named Ranges in MS Excel

<Names>
  <NamedRange ss:Name="Country"
              ss:RefersTo="=TableC5.1!R6C1:R86C1" />
  <NamedRange ss:Name="Data"
              ss:RefersTo="=TableC5.1!R6C3:R86C11" />
</Names>

• Close vocabulary can be used by even non-experts
• Minimal overhead marks data semantically and even simplifies usage of data within Excel documents
• Indexable and reusable via search engines in intra- and extranets
• Transformation to RDF as well as to µFormats, e.g. via Gleaning Resource Descriptions from Dialects of Languages (GRDDL) [8]

What to expect?

• Standardization (part of XHTML 2) vs. a group of Web 2.0 developers getting things done
• Possible developments in the future
  • Usage of µFs increases drastically
  • Usage of µFs and usage of RDF(a) increases, which may split the community
  • µFs disappear
• Development is viral
• Currently, µFs are early adaptors of the semantic-data in XHTML
• µFs may help to become Semantic Web reality

References

• [1] Microformats — The Next (Small) Thing on the Semantic Web?, IEEE Internet Computing, Rohit Khare, February 2006
• [2] hReview in Review — Purpose - Predecessors - Specification - Implications, CommerceNet Labs, Rohit Khare, May 2005
• [3] Live Clipboard Technical Introduction, Ray Ozzie, May 2006
• [4] RDFa Primer 1.0 — Embedding RDF in XHTML — W3C Working Draft 16 May 2006, Ben Adida, and Mark Birbeck, May 2006, Ray Ozzie, May 2006

References (cont'd.)

• [5] RDFa vs. Microformats, Evan Prodromou, May 2006
• [6] Microformats #1: Eine Einleitung, Sebastian Küpers, May 2006
• [7] What's the Next Big Thing on the Web? It May Be a Small, Simple Thing — Microformats, Interview with Tantek Çelik at the Supernova 2005, July 2005
• [8] Adding Semantics to Excel with Microformats and GRDDL, mnot's Web log, Mark Nottingham, May 2006

Questions?

Thank you for your attention!

Q & A