What's the difference between Control.Select() and Control.Focus()?

In WinForms, to set focus to a specific control, I always seem to wind up calling Control.Select() and Control.Focus() to get it to work.

What is the difference, and is this the correct approach?

Focus() is the low level function that actually sets the focus.

Select() is a higer-level method. It first looks iteratively upward in the control's parent hierarchy until it finds a container control. Then it sets that container's ActiveControl property (to the called control). The logic in those methods is not straightforward however, and there is special handling for UserControl containers.

Focus is a low-level method intended primarily for custom control authors. Instead, application programmers should use the Select method or the ActiveControl property for child controls, or the Activate method for forms.

http://msdn.microsoft.com/en-us/library/system.windows.forms.control.focus.aspx

For an example of how they are different, if you are trying to set a control for a Forms App to default focus to when you open it, only Select() will work when called in the constructor after InitializeComponent(). Focus() will not.