A header is an image that goes across the top of the screen on a website and useally contains the tittle of the website and can also contain navigation links for the website.
 A banner is a image that is usually an advertisement and contains a link to whoever the advertiser is. banners are often used to monetize a website and there is no one specific location to place a banner although across the bottom of the screen or on the right or left hand margins are common places.


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