The methods and procedures governing the way that information is exchanged between the user and the computer system. It involves the consistent formatting of prompts, check boxes, lists of options, sliders, messages, and other constructs. There are modal dialogs, where the user can do nothing else until the action required to satisfy the dialog has been taken; this can be as simple as acknowledging a message. Conversely, a modeless dialog is one that may be returned to after attending to other matters. See also dialog box.