ar site. For example, if someone searches for Greek restaurants in San Francisco, the Google engine looks at and ranks the restaurants partially on how many sites link to particular www.TechnicalPDF.com Greek restaurants in San Francisco and the type of sites linking to it. Google not only earns the highest search-engine- based advertising revenue in the United States, but because of its many acquisitions, it has the potential to skew results of searches in favor of its own sites. When search results are returned, search engines such as Google can rank their own sites higher than those of competitors. Google's search engines are located in hundreds of countries worldwide in addition to its presence in the United States. Over the years, Google's owner Alphabet acquired many software companies, including the following: Zagat (restaurant and hotel reviews) Android operating system software for smartphones Adsense (Google's network for advertising sales) DoubleClick (advertising network used to target ads to particular classes of people) Google Maps (GPS plus local guides and advertising) Keyhole Technologies, Zipdash Inc., and Where2 LL2 (software that forms the basis of Google Maps) ITA (airline flight aggregation information) Motorola Mobility (mobile devices; patents for mobile services) YouTube (online videos and streaming TV) Waze GPS (global positioning service) Zipdash (now part of Google's location services) In addition to possibly skewing search results toward their own sites, search engines have implications for privacy. Marketers can determine the following based on terms people search on: Gender Income Range Health Type of computer (Mac or Microsoft Windows) Location This information may be shared with advertisers who target ads at particular demographics based on search www.TechnicalPDF.com history. For example, they might show pop-up and sidebar ads on the Internet based on people's purchasing history. See the section "Privacy" below. Search Engines-Mathematical Algorithms and Page Ranking Google, a un