Dynamic Ads in Adsense - What do they mean?

So I was looking at my Adsense Panel today and checking reports for Last month. I sorted the ads by their Ad size and noticed that maximum number of Page views were for Ad Type Dynamic. But those Ads made me very less revenue, compared to Ad sizes of 728X15 and 335X280.

I though i should get rid of Dynamic Ads, but then i didn't know what they actually are and where do they appear on my website.

Dynamic Ads in Adsense

Apparently Dynamic Ads are the ads that appear in your Feed when you have adsense enabled for it. More the number of items in your feed more are the chances of dynamic ads appearing in your feed. By Dynamic they mean, the size of the image varies depending on your feed content. Please note that actual CPM for dynamic ads is very low and reason behind it is that adsense place those ads for you in your feed and it might not be at the best of places to get you maximum clicks.