SEM, CPC. Search Engine Marketing

When you buy key words through Google Adwords you can choose if your ads get displayed outside of the traditional Google search results. If you choose for you ads to display beyond the Google results they will be displayed on web sites that are part of the Google Adsense network.

In this example, ads from Google’s Adwords are displayed on CNN.com.

Anyone with a website can sign up to be a part of the Google Adsense network. And I mean anyone — and everyone trying to make a couple bucks off their web site does. That means your ads could show up on “junk” sites that don’t convert into paying customers.