What is an Ad Unit?

An ad unit is any type of ad that is displayed on a platform to users in order to monetize traffic.  There are several types of ad units, such as banner ads, offer wall ads, interstitial ads, and so on.  Each different type of ad unit looks and behaves differently.   Often, ad units are given names such as “skyscraper” and “leaderboard” which define the ad size, shape, and type.  Typically, the best ad units look like they’re part of the page.