Most visual controls can display context-sensitive Help as well as fly-by hints at runtime. The HelpContext and HelpFile properties establish a Help context number and Help file for the control. 

The Hint property contains the text string that appears when the user moves the mouse pointer over a control or menu item. To enable hints, set ShowHint to True; setting ParentShowHint to True causes the control's ShowHint property to have the same value as its parent's.