SEM stands for Search Engine Marketing is a form of Internet Marketing that involves the promotion of a Website by increasing its Traffic, Ranking and Visibility in Search Engine Results Pages (SERPs) primarily through paid advertising in Today's Competitive Marketplace.
Google Ad Words is the most popular paid search platform used by search marketers, followed by Bing Ads. Beyond that, there are PPC advertising options on the major social networks. Typically, SEM and PPC advertising is carried out through search engines, who charge advertisers a predetermined amount of money every time their ad is clicked.