Search engine marketing Search engine marketing Search engine marketing (SEM) is a form of Internet marketing that involves the promotion of websites by increasing their visibility in search engine results pages (SERPs) primarily through paid advertising. SEM may incorporate search engine optimization (SEO), which adjusts or rewrites website content and site architecture to achieve a higher ranking in search engine results pages to enhance pay per click (PPC) listings. In 2007, U.S. advertisers spent US $24.6 billion on search engine marketing. In Q2 2015, Google (73.7%) and the Yahoo/Bing (26.3%) partnership accounted for almost 100% of U.S. search engine spend. As of 2006,
Distributed search engine Distributed search engine A distributed search engine is a search engine where there is no central server. Unlike traditional centralized search engines, work such as crawling, data mining, indexing, and query processing is distributed among several peers in a decentralized manner where there is no single point of control. In April 2000 several programmers (including Gene Kan, Steve Waterhouse) built a prototype P2P web search engine based on Gnutella called InfraSearch. The technology was later acquired by Sun Microsystems and incorporated into the JXTA project. It was meant to run inside the participating websites' databases creating a P2P network that