Search Engine Marketing (SEM) is defined as the advertisement which is other wise termed as sponsored links. These advertisements are usually bought from Yahoo (YSM) and Google Sponsored Links. Search Engine Marketing is also termed as Advertising, where you advertise your product and services on various top search engines like Google, Yahoo, and MSN. Here the advertisement cost is based on the click that has been made on your advertisements. SEM ads could be viewed as quickly as you have done the payment online for the ads, where as the SEO is a long run and permanent solution for getting your website listed in search engines for an organic search.

For Example:
if you have taken a package of Rs. 2000/- and set the budget of Rs. 200 per click for a specific keywords, then 5 hits on your advertisement placed through sponsored ads would detect an amount of Rs. 1000/- from your account balance of Rs.2000/-.

Visibility of Ads
These ads are normally placed on the right hand side of the search page. Whereas the results on the left hand side of the pages are through organic search and nonpaid listings.