Every medium has its ad standards, like the 30-second spot in television or one-quarter page ad in print. Because the web started as a page-based medium, online advertising originated by dividing the page into defined units that serve as containers for display advertising. These started small, as clickable text buttons and banners, and then expanded into a variety of shapes and sizes. Technology advances in ad creation and ad serving, coupled with widespread broadband penetration, are beginning to fill these containers with everything from clickable print ads and graphics pictures that push advertising to richly interactive brand experiences that pull consumers in, engage them, and prompt them to take actions marketers desire. Some are reaching levels of sophistication so high that consumers need not leave the site they are visiting to have their activity interrupted by a side trip to a brand’s website.
The Interactive Advertising Bureau (IAB) recognized that standard ad sizes were needed to initially develop the market and, with industry consultation, created a set of specifications. Those specs were formalized as voluntary guidelines. Now widely adopted, they serve their purpose, bringing consistency to ad specifications, ad buying, and ad serving while leaving creative executions wide open and virtually unlimited. Biannually reviewed, the guidelines are revisited and refined, ensuring their freshness and fit with advertising practices.