More InformationWindows Interface Components - Windows
Because windows provide access to different types of information, they are classified according to common usage. Interaction with objects typically occurs in a primary window where most primary viewing and editing activity takes place. In addition, multiple supplemental secondary windows can be included to allow users to specify parameters or options or to provide more specific details about the objects or actions included in the primary window.
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For more information about secondary windows, see Chapter 9, "Secondary Windows."
Fundamentals of Designing User Interaction
Design Specifications and Guidelines