If you do not know what Google AdSense is than you must be living under a rock reading this off of a piece of papyrus someone printed it out on! For those who know of it but not exactly what it is let me tell you now that AdSense is a program in which a webmaster runs small bits of advertising that come from the Google AdWords program.
AdSense is the publisher side of the Google business (do you really think search makes money?) AdWords is the advertiser side of that business.
Some have speculated that Google likes to penalize advertisers who do not use AdWords by lowering the positioning of their pages when certain keyword searches are done. The idea behind that conspiracy theory is that Google would not be able to make as much money as it does now if it allowed a commercial site to be on top of the rankings for a certain keyword. These folks believe that Google wants commercial sites to appear in the sponsored link section rather than as organic search results simply because they can make more money that way.
At any rate I do use AdSense but I do not use AdWords. However, if you use both you must be very careful.
I recently came across a website that was running AdSense and one of the ads shown was for their own site! Curious I clicked on it. What do you think happened?
It refreshed the page!
Can you believe that Google's AdSense program actually allowed an ad to show up on the very page to which that ad is designed to take people? Believe it because it is true.
If you are using both services I highly recommend you keep an eye on your competitive ad filter settings. This filter allows you to list websites from which you do not want ads to appear. The idea is that if you run a website that sells flashlights you do not want ads for your competitors site to show up on yours. You can also use the filter to filter out low-paying or MFA (made for AdSense) sites.
For some foolish reason I thought the braniacs at Google would know better than to send ads to a site that are for that site! Then again these are the same brainiacs that recently sold digital movies to their customers, revoked those same videos and then offered their customers a $5 bonus to make up for it.
So please, use your competitive ad filter to block your own AdWords ads!