An interstitial (something "in between") is a page that is inserted in the normal flow of editorial content structure on a Web site for the purpose of advertising or promotion. It can be more or less intrusive and the reaction of viewers usually depends on how welcome or entertaining the message is. An interstitial is usually designed to move automatically to the page the user requested after allowing enough time for the message to register or the ad(s) to be read.
Several variations have been identified:
(1) The splash page , a Web page, usually containing an animated image, that is linked to briefly when you click on or enter a site's home page address. Wired Magazine's Web site has used this kind of interstitial.
(2) The game, "You Don't Know Jack" inserts animated ad interstitials into its game. The ads are clever and users don't seem to mind them in the context of one of the Web's more enjoyable games.