The contents and properties of an interactive form are defined by an interactive form dictionary that is referenced from the AcroForm entry in the document catalog in the PDF file.
Websites, either static (product catalogs for example) or interactive (like with order entry).
网站，或者是静态的(比如产品目录)或交互式的(比如订单输入)。
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The Secret Device is an entry point for the Hellboy II alternate reality game. An interactive combination lock that reveals clues, hints and player direction.