Banner blindness is the tendency of people to ignore banner ads on Web sites. In 1998, Benway and Lane, a research team, reported the results of studies requiring users to find information located in banner ads. Contrary to the prevailing marketing philosophy that the larger an item on a Web page, the greater its perceived visual importance and likelihood of attracting attention, Benway and Lane found that users had more difficulty finding information when it was located in a banner ad. Benway and Lane called this phenomenon "banner blindness." Experts believe that banner blindness occurs because experienced Web users are in "search mode" and tend to ignore banner ads as irrelevant for their search.
Today, one index of the effectiveness of a banner ad is its click-through rate, a percentage calculated by dividing the number of times a banner ad appears on a site by the number of times the ad is clicked on. Although experts agree that banner blindness is probably the main cause of low click-through rates, other studies have shown that banner ads are recognized by users and provide branding value for the advertiser.
Also see: Advertising terminology on the Internet