Google Ranking - Indexed Pages

POSTING LISTS
Google's index contains billions of webpages. Each page is assigned a reference number.

Every word on every web page is indexed. This means that the reference number for the page is indexed for every distinct word on the page.

This allows search terms to be found without scanning all the text on every web page in Google's index.

Hundreds of servers work together to find indexed data for each search phrase queried. Initially pages containing any word in the search phrase are placed in individual posting lists.