5. Definition
‣ 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) through optimization (both
on-page and off-page) as well as through
advertising (paid placements, contextual
advertising, and paid inclusions).
source: http://en.wikipedia.org/wiki/Search_engine_marketing
20. Definition
‣ Search engine optimization (SEO) is the
process of improving the visibility of a
website or a web page in a search engine's
"natural" or un-paid ("organic" or
"algorithmic") search results.
source: http://en.wikipedia.org/wiki/Search_engine_optimization
28. Definition
‣ Search Advertising is a method of placing
online advertisements on Web pages that
show results from search engine queries.
Through the same search-engine
advertising services, ads can also be placed
on Web pages with other published
source: http://en.wikipedia.org/wiki/Search_advertising