For the past two decades, legions of computer users learned how to create files, place them in folders, and dispose of them in a trash can. They used their computers to send messages by placing them in a virtual envelope addressed to their recipients. The desktop and mail metaphor provided new computer users with a context and frame of reference they were familiar with and helped them learn how to make effective use of their computer. However, the days of relying on metaphors based on paper-based processes when designing software may soon be coming to an end.
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