Google AdSense is an advertising placement service by Google in which website owners can display advertisements on Web sites and earn revenue. It serves automatic text, image, video, or interactive media advertisements that are targeted to site content and audience.This can easily be integrated into any site. There are two ways to make money from AdSense:

Impressions – this is based on the number of page views of pages or posts with ads
Clicks – this is based on how many people click on the ads.  » Read more about: How to Add Google AdSense in Your Website  »