Search Engine Marketing (SEM) is a crucial internet marketing strategy focused on boosting website visibility in search engine results pages (SERPs), primarily through paid advertising, often integrated with Search Engine Optimization (SEO). This powerful field has experienced rapid growth, with U.S. advertisers spending $24.6 billion in 2007, and by 2015, Google commanded a dominant 73.7% share of U.S. search ad spend.

Evolving from early pay-per-click programs launched by companies like Open Text (1996) and Google AdWords (2000), the comprehensive term SEM was popularized by Danny Sullivan in 2001. Google's market dominance became so pervasive, reaching 89.3% globally by 2016, that in August 2024, a court declared its monopoly status, accusing it of illegally cornering the market and harming online publishers and advertisers. Ultimately, SEM also functions as a vital business analytics tool, helping organizations identify market opportunities, optimize marketing efforts, and drive customer acquisition.