Question

What is the usefulness of W3C’s Semantic Data Extractor?

http://www.w3.org/2003/12/semantic-extractor.html

This tool, geared by an XSLT
stylesheet, tries to extract some
information from a HTML semantic rich
document. It only uses information
available through a good usage of the
semantics defined in HTML.

The aim is to show that providing a
semantically rich HTML gives much more
value to your code: using a
semantically rich HTML code allows a
better use of CSS, makes your HTML
intelligible to a wider range of user
agents (especially search engines
bots).

As an aside, it can give clues to user
agents developers on some hooks that
could be interesting to add in their
product.

After checking validation for CSS and HTML. Should i go for Semantic Data Extractor tool.

What it does. and how it can improved our coding.? Is anyone using it?

And i check some site randomly with but with most of sites it gives error

Using org.apache.xerces.parsers.SAXParser
Exception net.sf.saxon.trans.XPathException: org.xml.sax.SAXParseException: The element type "input" must be terminated by the matching end-tag "`</input>`". 
org.xml.sax.SAXParseException: The element type "input" must be terminated by the matching end-tag "`</input>`".

Is it possible to get validate every site with this tool?

Answer 1

After checking validation for CSS and HTML. Should i go for Semantic Data Extractor tool.

Probably not

What it does.

Exactly what you quoted from its homepage.

and how it can improved our coding.?

Other then hitting you over the head when you have problems counting heading levels; not a lot.

And i check some site randomly with but with most of sites it gives error

It depends on well formed and sane input.