See links below for the latest and greatest ad networks that explain the different styles and pay rates for ads. CPM = cost per THOUSAND impressions. So a $0.50 CPM would be 50 cents for 1000 impressions. Based on Hubski's pageviews yesterday, we would make a few bucks (literally) if we had those on every page you all viewed. $0.50 is really high though. Usually it's much, much less. The way I've said it up there isn't technically correct though. It's usually said, "the advertiser pays a $10 CPM to run 100,000 ads (a $1,000 total expense)." But then you have to look at what the RPM (revenue) actually is. Since you are using an ad network, the cost may be $1000 but you, as the "publisher" or whatever, only sees $500 because the network takes the other $500. [1] http://www.monetizemore.com/blog/10-best-ad-networks-2014/