wikipedia.org defines Search engine marketing, or SEM, is a form of Internet marketing that seeks to promote websites by increasing their visibility in search engine result pages (SERPs). According to the Search Engine Marketing Professional Organization, SEM methods include: search engine optimization (or SEO), paid placement, contextual advertising, and paid inclusion.^[1] Other sources, including the New York Times, define SEM as the practice of buying paid search listings.^[2][3]