[AbiDrew85]

, it means Search Engine Optimization. It is the mojo used to get Web sites and pages to the top of search pages, like on google or bing.

Without just buying the "prime" space outright. Some companies do... Though I usually ignore their ads. Google at least DOES clearly tell you those spaces are reserved for paid "results".

Most companies that do that though also do use SEO as well to try and get their web site up there in the normal rankings as well.