Ad banners (also known as banner ads) are one of the most dominant forms of advertising on the internet. Banner ads are a form of display advertising that can range from a static graphic to full motion video. History

HotWire ran the first banner ad on October 24, 1994. The banner ad was for AT&T's "You Will" campaign, and was created by TANGENT communications of Westport, Conn. Image:banner.JPG Although this ad has become known as the first banner ad, TANGENT Executive Producer Otto Timmons says: "There were at least five or six other banner ads that launched at the same time and they too should get credit for being "first". I can remember Club Med, AT&T, ZIMA. Last but not least, O'Reilly's Global Network Navigator, GNN, started accepting paid advertising at the same time (one banner ad on the home page, as I recall)." Present day outlook

As of Tuesday, December 23, banner advertising is poised for flat growth in 2009, after years of double-digit growth. This plays in concert with weak estimates for all forms of advertising -- both online and offline. Despite a gloomy outlook in the short term, display advertising is projected to account for over $12.3 billion in 2009. IAB Guidelines

Banner ads today can of a variety of file formats. From static JPEG and GIF banners to In-Banner Video Ads and rich media units. The IAB frequently updates their ad guidelines in order to assist creators and buyers of banner ads. See the IAB's Ad Unit Guidelines for voluntary guidelines for banner ads. By far, the most standard banner ad sizes are (by pixel dimension): ;300x250 :Also known as a super-square, tile or big box. Best practice is to refer to the ad by its pixel dimensions, 300x250, to avoid ambiguity. ;728x90 :Also known as a billboard, banner or super-banner. Best practice is to refer to the ad by its pixel dimensions, 728x90, to avoid ambiguity. ;160x600 :Also known as a skyscraper. Best practice is to refer to the ad by its pixel dimensions, 160x600, to avoid ambiguity. Media planning and buying

Compared to offline forms of display advertising, banner ads allow for several enhanced types of targeting. Including geo-targeting, dayparting, and various types of Behavioral Targeting. Media planners are able to use these types of targeting to better reach their desired audiences. Traditional demographic is important as well. Buying banner ads is most often, and almost exclusively, done on a CPM basis. CPMs for banner ads can range from less than $1 to upwards of $100 or more. CPMs depend on the level targeting detail, and the perceived value of the audience. Measurement and tracking

In addition to enhanced targeting possibilities, banner ads -- like all digital advertising -- allow for detailed measurement and tracking. Below are some of the measurements used with banners: ;Impressions :Each banner ad impression -- measured as a load in a web user's browser -- is tracked. Advertisers are sure that their ad has loaded; whether that correlates into a "real" impression is up for debate. ;Click rate or click-through rate :The click-through rate is the most-often used metric for success in online advertising. As banner ads are both clickable and branding units, there is discussion as to whether this is the best success metric for banner ads. ;Conversions :More important than click-throughs are conversions, which gauge whether a web user has taken the actions defined as a success for each campaign. Conversions can include: signing up for an email list, watching a branded video, downloading a coupon, or purchasing a product or service. ;Interaction rate :As banner ads have become more interactive and engaging, advertisers have used rich media to interact with web users instead of simply asking them to click-through to another website