How to Read Search Engine Results Pages
Check out shopping results.
It’s often not hard for the search engines to figure out when someone is quite likely searching for a product he may be interested in buying. If someone searches for shoes, it’s quite likely he’s interested in buying a pair, either offline (that’s where the Local results come in) or online (that’s where the Shopping results come in).
On the other hand, if someone searches on shoe manufacturing victorian england, it’s unlikely that he’s in the market for a pair.
The major search engines all maintain product indexes, totally separate from the organic or even the PPC indexes.
When a search engine figures you may be looking for product information, it inserts product results — typically with images — into the search-results page. Clicking the Shopping search results leads into the search engine’s shopping area, where the searcher can find more information about these, and other, products.