Control Help Using ToolTips
You can use the ToolTip component to display a brief, specialized Help message for individual controls on Windows Forms. The ToolTip component provides a property that specifies the text displayed for each control on the form. For more information about working with the ToolTip component in this way, see How to: Set ToolTips for Controls on a Windows Form at Design Time. Additionally, you can configure the ToolTip component so that there is a delay before it is shown. For more information, see How to: Change the Delay of the Windows Forms ToolTip Component.