With growing technology, it has become easier to find any and everything on the Internet and the search engines play a vital role in helping people find relevant information.
Most Businesses have set up their websites and try to have their sites ranked high in the natural results of searches that are displayed to searchers. This will bring the maximum exposure possible, and the ability to attract plenty of potential customers/clients by using exactly what Google looks for in a domain name.
The SEO company has the job as we all know to determine the keywords frequently used by visitors, but SEO alone is not enough. You need to conduct marketing efforts online that are aimed at increasing the traffic and conversion.
SEM or search engine marketing encompasses search engine optimization, social marketing, pay per click campaigns and online visibility, which increase branding and recognition.
So in brief, the work of SEM is to promote your website in all the many other areas of website marketing other than SEO.