Tends to have more ad inventory available from advertisers, which can increase earnings when both text and image ads are enabled. Performs well if placed above the main content, and on forum sites. Suitable for text ads and display ads.
You need this to get it done:
You can create a responsive display ad, or upload a display ad. You can also choose to copy existing ads.
You can upload image ads as .gif, .jpg and .png
You can upload AMPHTML ads as a .zip containing 1 HTML document and up to 39 media assets.