Semantic HTML

Semantic HTML Dr. Harry Chen CMSC 491S/691S April 23, 2008

Agenda

Yet Another Semantic Web Presentation

Embed semantic description in HTML

Microformats

RDFa

Click to watch the video

Problem & Plausible Solutions

How should we publish semantic information on the Web?

One HTML page  One RDF document

Mix RDF into the HTML page

Extend HTML with new semantic tags

Microformats

Introduce semantics into Web pages by using XHTML tags with standard data format vocabularies

hCard (People & Organization)

hCalendar (Calendar & Events)

XFN (Social Networks)

rel-tag (tagging)

…

Microformats basics

Use standard XHTML attributes to describe information.

Mostly thru the “class” attribute

Sometimes thru the “id”, “title”, “rel” or “rev” attr.

As the webots process the pages, they reads information from those attributes.

For search indexing

Grabbing contact & social network information

Describe yourself using Microformats My Home Page

Find my name

Wrap my name in “fn”

“ fn” == Full Name in hCard

“ url” == my URL CSS Class (not MF)

http://harry.hchen1.com/contact-me/biosketch

What’s next? http://kitchen.technorati.com/contact/search

Another Example http://hchen1.com/contact-me/biosketch/ I live in Columbia Maryland.

Add Geo location Geo vocabulary comes from W3C Geo http://www.w3.org/2003/01/geo/

Prepare mashup data

Optimus is a Microformats data transformer.

Transform Microformatted page to

XML,

JSON or JSON-P

Implementation

One PHP file and Few XSTL

Let’s see a demo…

http:// microformatique.com/optimus /

RDFa

“ a” == “awesome” -- src:http://www.youtube.com/watch?v=ldl0m-5zLz4

“ a” == provide a set of “attributes” that can be used to carry metadata in an XML language

XHTML is XML

RDFa uses…

XML Attributes

“ about”

“ rel”

“ href”

“ property”

“ content”

“ datatype”

“ typeof”

Dublin Core example ( http://www.example.com/books/wikinomics , dc:title, “Wikinomics”) ( http:// www.example.com/books/wikinomics , dc:creator, “Don Tapscott”) ( http:// www.example.com/books/wikinomics , dc:date, 2006-10-01”) RDF Triples Source: http://en.wikipedia.org/wiki/RDFa

XHTML + RDFa

Let’s try something cool