How to make a structured-like web via those extensible markup language?

I’m not following your question.

I don’t see when you’d need an external XML file. There’s already XHTML which is HTML specified as XML, and microformats can extend that inline.

The capability already exists for the web to be structured, even without any of the additional markup formats you mention.

Write clear text. Make sure your (X)HTML is valid and structured meaningfully, and not just tag soup. Use meaningful class and element ID names. Bingo, you’re most of the way to the much-ballyhooed “Semantic Web,” and you’re already making Google happier.

@cwilbur & @Vincentt, so now we talking about XHTML, we view XHTML page on browser, and it just like normal HTML right? so the purpose is for search engine, feed reader(??) and etc. to easily read/extract the data out? or is there any other useful purpose?

@glial, i am sorry :( but my question was about structured web(web as database).

Let say a blog entry, we have basic information: TITLE, CONTENT, AUTHOR, DATE/TIME, TAG….then we create RSS file for instance. So my “problem” now is…except RSS, ATOM…what other purpose?

can anyone copy and paste some sample code will make the blue jellyfish above happier.

Sample code for what?

Earlier, you seemed to be asking how to do semantic markup. Now, you seem to be asking why to do semantic markup. It’s so that automated processes can infer the content of the document and index it appropriately.

That may not seem like a lot, at least until you start having vice presidents ask why your site isn’t on the front page of Google search results even after spending $40,000 per month on “search engine optimization” for the past year.

And if that’s not your question, I’m sorry, but I’m having a hard time making sense of your postings.

@tantaikooi – XHTML defines (at least, if the author adheres to standards) the meaning of whatever is within a tag. For example, ”<title>This is a title</title>” defines that “This is a title” is, in fact, a title. This allows for web browsers to display the text as a title (i.e. in the titlebar), for search engines to recognise it as a title, for screenreaders to read it as a title, etc.

Now RSS/Atom is also an XML format, which has not much to do with HTML, that contains the latest updates of a particular page, which is meant to be read by machines to be able to quickly determine when something new has been posted.

Unfortunately, as with cwilbur, I’m also having a hard time figuring out the actual question :(