AdSense is a Ad serving program run by Google. Website owners can enroll in this program to enable text, image advertisements on their websites. AdSense allows website owners to display contextual adverts sourcing PPC ads from AdWords. Publishers are paid for every click made on the ads.

AdSense is the Biggest PPC contextual advertising publishing system you can find today. thoundas of publishers earn money online using AdSense ads in their web sites. Due to concerns about click fraud AdSense program is very strict about their TOS. Publishers get banned for even slightest mistake they make. You need to apply for AdSense account with your website or blog and it take 24 hours to 2 weeks getting approved. Web site or blog you apply has to be at least few months old and full of content or you might be rejected.