Online Advertising

ALSO CALLED: Pop-up Ads, Web Advertising, Internet Advertising
DEFINITION: A pop-up ad is a pop-up window used for advertising. When the program is initiated by some user action, such as a mouse click or a mouseover, a window containing an offer for some product or service appears in the foreground of the visual interface. Like all pop-ups, a pop-up ad is smaller than the background interface - windows that fill the user interface are called replacement interfaces - and usually  … 
Definition continues below.

ONLINE ADVERTISING DEFINITION (continued): …  resembles a small browser window with only the close, minimize, and maximize options at the top. A variation on the pop-up ad, the pop-under, is a window that loads behind the Web page that you're viewing, only to appear when you leave that Web site. Pop-up ads are not popular with the average Web surfer, and there are several products that disable them, such as Pop-up Stopper, Pop-up Killer, and Pop-up Annihilator. One thing to look for in such a program is the ability to differentiate between user-initiated pop-up windows and others, because many other applications (such as Webcasts, for example) … 
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