Integrating User Help in Windows Forms
An essential, but often overlooked, aspect of building Windows-based applications is the Help system, as this is where users turn for assistance in times of confusion. Windows Forms support two different types of Help, each provided by the HelpProvider Component (Windows Forms). The first involves pointing the user to a Help file of either HTML or HTML Help 1.x or greater format. The second can display brief "What's This"-type Help on individual controls; this is especially useful on dialog boxes. Both types of Help can be used on the same form.
Additionally, the ToolTip Component (Windows Forms) can be used to provide individual Help for controls on Windows Forms.