Let's be honest here: I'm a mom, I'm an entrepreneur, I'm a small-business owner, I'm a blogger ... I'm a lot of things, but I'm not an expert at online advertising. That said, I have experimented a lot with ads on my websites, and I get a lot of email on the subject, so I thought I'd share my experiences with you.
Let's start with the King of them all: Google.
I have only used Google AdSense for Content; I haven't tried the AdSense for Search or Referrals, or any of the other money-making programs Google offers.
AdSense for Content is everywhere; I'm sure you're familiar with it. It's easy to set up: Google generates a snippit of code you can paste into your webpages and blogs. Google then "crawls" your site scanning the content, and displays text or banner ads that are supposed to relate to what you're talking about or selling. As such, Google AdSense never did very well for me on my personal blog, Kerflop. My AdSense for Content ads always displayed really rather odd things that didn't necessarily interest anybody -- I think it's because I don't write about any one specific topic.
With AdSense for Content, people have to actually click on your ads in order for you to make money. The higher the traffic your website, the better the chance of people actually clicking on an ad.
Kerflop gets between 1,200 and 2,500 unique hits per day; AdSense for Content ads make me about $80 per month. I place them on some of my most-highly trafficked pages, which gives me a better payout than when they were placed on my main pages. But it's still nothing to write home about.
AdSense for Content works much better on my business website, Very Baby. Since this site has a very specific topic (cloth diapers, and cloth diaper sewing materials), the ads are very relevant to my customers. I make $200 to $250 a month from ads on my business website, even though I receive much less traffic there than I do at Kerflop.
A common misconception about AdSense for Content is that you have no control over your ads. You do. You can log in to your Google account and block any ads you deem inappropriate. I block ads for disposable diapers, and any ads that are advertising adult diaper/adult baby fetishist sites or products. I do not block ads from competitors, because I honestly feel there is enough room for all of us and if we don't have something a customer is looking for, maybe one of my advertisers does. Though, I may change my tune if the cloth diaper fabric industry becomes more fiercely competitive. Stop that, I heard you laughing. It… you know, it might!