So those are the traditional flight and hotel search websites that are essentially online travel agencies. The hotel price comparison websites are not agencies, because they search for and compare prices between the different sites like Expedia and Laterooms. It's true that the first part of a search is the same, in that when you select the destination city, dates and number of people, they tell you what hotels have availability. But the next stage is when they retrieve prices from numerous merchants, and then provide the links to those merchants who are able to offer the hotel room for the cheapest price.This latter sort of comparison website do not actually sell anything to the consumers, they provide a free service to enable people to find the best deal.