The number of types of banners and sizes have proliferated. In a recent survey, IAB members stated that this proliferation of banner types and sizes is inefficient and confusing and that identifying a baseline model would result in benefits for both buyers and sellers of advertising on the Web. The two groups also recognize that Web sites which chose to implement these models may wish to do so over a period of several months to allow those who sell space or create banner content to make any adjustments.
Banners are currently the primary form of Internet and interactive advertising.