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,
Trip (search engine) This is a repository of clinical Q&As from a variety of Q&A services. At launch it had over 5,000 Q&As and currently has over 6,300. This content has been integrated into Trip. Trip (search engine) Trip is a free clinical search engine. Its primary function is to help clinicians identify the best available evidence with which to answer clinical questions. Its roots are firmly in the world of evidence-based medicine. The site was created in 1997 as a search tool to help the staff of ATTRACT answer clinical questions for GPs in Gwent, South Wales. Shortly afterwards "Bandolier" highlighted the