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Information in an on-line display that is not immediately useful, but contributes to a viewer's gestalt of what's going on with the software or hardware behind it. Whether a given piece of info falls in this category depends partly on what the user is looking for at any given time. The "bytes free" information at the bottom of an MS-DOS "dir" display is tourist information; so (most of the time) is the TIME information in a Unix "ps(1)" display.