<P> The banner ad played a significant role in enabling the rapid development of paid advertising on the Internet . With the standard formats, operation (clickable link to a destination), and pricing system (impressions), the banner ad enabled any Web site to sell advertising, and provided the operating requirements for ad server companies, such as NetGravity, to develop the systems needed to operate and track Web - based advertising . The banner ad was also unique, as compared to advertising appearing in then comparable media, such as newspapers and magazines . Unlike advertising in periodicals, the banner ad encouraged media consumers to actually leave the media service or product and go to a separate media environment (typically a Web site operated by the advertiser). In contrast, readers viewing newspaper or magazine advertising are not encouraged to leave the periodical . Rather, the message of the advertising is itself intended to influence the reader . </P> <P> Ad sizes have been standardized to some extent by the IAB . Prior to the IAB standardization, banner ads appeared in over 250 different sizes . However, some websites and advertising networks (outside the Eurosphere or North America) may not use any or all of the IAB base ad sizes . The IAB ad sizes are: </P> <Table> Sizes in bold are part of the IAB's Universal Ad Package . <Tr> <Th> Name </Th> <Th> Width / px </Th> <Th> Height / px </Th> <Th> Aspect ratio </Th> </Tr> <Tr> <Th_colspan="4"> Rectangles and Pop - Ups </Th> </Tr> <Tr> <Td> Medium Rectangle </Td> <Td> 300 </Td> <Td> 250 </Td> <Td> 1.2 </Td> </Tr> <Tr> <Td> Square Pop - Up </Td> <Td> 250 </Td> <Td> 250 </Td> <Td> </Td> </Tr> <Tr> <Td> Vertical Rectangle </Td> <Td> 240 </Td> <Td> 400 </Td> <Td> 0.6 </Td> </Tr> <Tr> <Td> Large Rectangle </Td> <Td> 336 </Td> <Td> 280 </Td> <Td> 1.2 </Td> </Tr> <Tr> <Td> Rectangle </Td> <Td> 180 </Td> <Td> 150 </Td> <Td> 1.2 </Td> </Tr> <Tr> <Td> 3: 1 Rectangle </Td> <Td> 300 </Td> <Td> 100 </Td> <Td> </Td> </Tr> <Tr> <Td> Pop - Under </Td> <Td> 720 </Td> <Td> 300 </Td> <Td> 2.4 </Td> </Tr> <Tr> <Th_colspan="4"> Banners and Buttons </Th> </Tr> <Tr> <Td> Full banner </Td> <Td> 468 </Td> <Td> 60 </Td> <Td> 7.8 </Td> </Tr> <Tr> <Td> Half banner </Td> <Td> 234 </Td> <Td> 60 </Td> <Td> 3.9 </Td> </Tr> <Tr> <Td> Micro bar </Td> <Td> 88 </Td> <Td> 31 </Td> <Td> 2.84 </Td> </Tr> <Tr> <Td> Button 1 </Td> <Td> 120 </Td> <Td> 90 </Td> <Td> 1.33 </Td> </Tr> <Tr> <Td> Button 2 </Td> <Td> 120 </Td> <Td> 60 </Td> <Td> </Td> </Tr> <Tr> <Td> Vertical banner </Td> <Td> 120 </Td> <Td> 240 </Td> <Td> 0.5 </Td> </Tr> <Tr> <Td> Square button </Td> <Td> 125 </Td> <Td> 125 </Td> <Td> </Td> </Tr> <Tr> <Td> Leaderboard </Td> <Td> 728 </Td> <Td> 90 </Td> <Td> 8.09 </Td> </Tr> <Tr> <Th_colspan="4"> Skyscrapers </Th> </Tr> <Tr> <Td> Wide skyscraper </Td> <Td> 160 </Td> <Td> 600 </Td> <Td> 3.75 </Td> </Tr> <Tr> <Td> Skyscraper </Td> <Td> 120 </Td> <Td> 600 </Td> <Td> 5 </Td> </Tr> <Tr> <Td> Half page ad </Td> <Td> 300 </Td> <Td> 600 </Td> <Td> </Td> </Tr> </Table> <Tr> <Th> Name </Th> <Th> Width / px </Th> <Th> Height / px </Th> <Th> Aspect ratio </Th> </Tr>

What are the dimensions of a website banner
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