Digital Display Advertising is a form of online advertisements. They are essentially what we used to refer to as “banner ads”. Over time display ads have gone through many different iterations. At one point you always saw 466 pixels wide by 66 pixels tall, then came Macromedia (now Adobe) Flash advertisements, and finally you now see both desktop and mobile display advertisements run on all sorts of advertising platforms. These platforms include programmatic tools like Aquity and Rocket Fuel.
Now you can run Display Banner Ads in a variety of dimensions from leaderboards to big box ads and mobile (responsive) HTML5.
Typically display ads are displayed on content networks such as Google Adsense.