From where does Google get the abstract for each of its site results, that it displays on its search result page? - metadata

Question

I am working on a project in which i have to search for terms on a search engine and then cluster the results on their contextual sense. So i have to treat each result as a document. unfortunately, the data present along with each result on the result page is too little for clustering. Hence, I wanted to know from where the search engines get the abstract for each result that they show. If i could get that entire abstract then i can cluster the results by treating them as separate documents.
From where does google get the abstract ?
For eg: If you search for "1000 Mile" on google, the second result shows the following abstract:
"The women's 1000 Mile Collection is based on classic designs and reflects Wolverine's long heritage of crafting quality footwear. Complementing these classics ..."
This abstract is not present in the Meta tags of the page.
From where does Google find this data.
Thanks

Answer 1

From Does Google use the Meta Description Tag for Description of Page?
Google will choose your search results snippets from the following places (not necessarily in this order):
The page's Meta Description tag
The page's Open Directory Project (ODP) Listing
Page content relevant to the search query
If you do not want Google to use the ODP listing's description then you can tell them not to do so with the following Meta tag:
<meta name="robots" content="NOODP">
If you want to encourage Google to use your Meta Description tag then make sure it is unique to each page. Also make sure it contains an accurate description of the page's content.
In thew absence of an ODP description and Meta Description tag, Google will use a portion of the page's text as the description. This text will contain the closest matches to the search query. I have not seen any official limit to how long this can be but a couple of sentences seems about right.
On a related note, if you don't want a snippet to be shown with a particular page you can use the following Meta tag to prevent one from being shown:
<meta name="robots" content="nosnippet">
See this blog post for Google's tips on using the meta description tag.
According to this site, "The meta description should typically be at most 145 to 150 characters in length as these are the maximum number of characters typically displayed at Yahoo! and Google, respectively."

Answer 2

That site is Flash-based, and Google can index Flash content, so given that the snippet isn't in the HTML source of the page as you point out, nor is it in the cached version of the page, I'm guessing that it's somewhere in the Flash movie.
It's kind of arbitrary that the snippet mentions 'The women's 1000 Mile Collection' while the site link itself is to the parent category of 1000 mile, not just women's, so I'm guessing here that gathering snippet-friendly metadata from a Flash site is an imprecise science. That's my best guess.
In this Google Webmaster blog post, they explain how they use external text or HTML files loaded into the Flash movie, and in one of the comments Jonathan Simon says (sorry):
"We try our best to crawl Flash content but the results can sometimes be less than ideal. You are only seeing a title in the search results for your site because that's the only bit of HTML text that you have outside of your Flash content. You could add a Meta description element to offer more information in HTML. You could also add some other text that's not a part of your Flash content. Just doing this should improve the snippet you see associated with your site in the search results."