The content-based adverts can be targeted for interest or context. The targeting can be CPC (click) or CPM (impression) based. There's no significant difference between CPC and CPM earnings, however CPC ads are more common. There are various ad sizes available for content ads. The ads can be simple text, image, animated image, flash, video, or rich media ads. At most ad sizes, users can change whether to show both text and multimedia ads or just one of them. As of November 2012, a grey arrow appears beneath AdSense text ads for easier identification.
