Learn what happens when you do a Google web search :
Here comes a great video from Google (by Matt Cutts), explaining broadly how the Google search works.According to Matt Cutts, when you do a Google search, you aren’t actually searching the web, you are searching only Google’s index of the web which may not include each and every web page from the internet.
Watch this video to learn more:
How Search Works
If you are curious about knowing how stuff works at Google, like how the Google search works or how search ads work or how Google Apps work, you may want to visit this how Google works page.
