SEM (Search Engine Marketing) is the process of gaining website traffic by purchasing ads on search engines.
"Search Engine Marketing" was once was used as an umbrella term to encompass both SEO (search engine optimization) and paid search activities. Over time, the industry has adopted the SEM acronym to refer solely to paid search.
At Search Engine Land, we generally use SEM and/or "Paid Search" to refer to paid listings, with the longer term of search marketing used to encompass both SEO and SEM. Below are some of the most common terms also used to refer to SEM activities:
SEM is the wider discipline that incorporates SEO. SEM includes both paid search results (using tools like Google Adwords or Bing Ads, formerly known as Microsoft Center) and organic search results (SEO). SEM uses paid advertising with AdWords or Bing Ads, pay per click (particularly beneficial for local providers as it enables potential consumers to contact a company directly with one click), article submissions, advertising and making sure SEO has been done. A keyword analysis is performed for both SEO and SEM, but not necessarily at the same time. SEM and SEO both need to be monitored and updated frequently to reflect evolving best practices.