I put the Adsense ads on my blog because someone told me that they make money from them every month. Well, I'd had them on my blog for over a year and I haven't made one penny from them...so as of today they are gone.
The way they work is when someone visits your site or blog and they click on one of the ads, you get a few cents or a dollar for each time someone clicks on them. But I've been to many websites where they ahve ads and not once have I ever clicked on one of the ads. So I guess many people are like me and don't. So they are gone.