the “feature” is called XML comments. Just type /// right before your methods and VS will generate some xml tags. These will be used to show the tooltip as well as parameter info aso.
/// <summary>
/// this will be the tooltip
/// </summary>
/// <param name="args">args will be passed when starting this program</param>
static void Main(string[] args)
{
}
Screenshot of my VS2010 when calling method add. As you can see, xml comments are shown.
