What if Hungry Howie's pizza ads are shown when an article regarding NCAA basketball in ESPN.com is read? Or what if French Onion soup ingredient products are shown when a blog regarding how to make a French Onion soup is read? That is Content-Driven Advertising.
With Content-Driven Advertising, you target your ads to IAB Categories or some keywords when you create your campaigns. When a page with content that matches the IAB Categories or the keywords is read, your ads are displayed.