Andrew Goodman is the author of 21 Ways to Maximize Your Profits on Google AdWords Select.

"The strength of Mike Grehan's guide is in its thorough research. Mike grills not only marketing experts but also scientists at today's leading search engines, as well as some researchers toiling away on projects you may never have heard of but which are definitely influential in 'insider' circles. Anyone who has an intellectual or material interest in how search engines work will benefit from his thorough treatment of the field. 'How Search Engines Work' slices through the layers of idle speculation and myths and gets right to the heart of the matter."