That's a very overall representation of how Google search works - ideal for anyone who want to understand how search engines, in general, dig out data. The real magic happens through the algorithms, which each search company guards like USA guards the Pentagon servers.

Google says that they analyse over 200 various parameters to figure out which URL lists over the others and gets more priority in search engine results for specific keywords. The latest hummingbird algorithm is said to be aware of the context of the searches and finds out sites that are authoritative and offer 'real help' for the search terms are listed on the top.