The Button is a class which contains various events one of which is the Click event. It also has properties which keep values about it's location, both on the form and on the screen. It also has a method which communicates with Windows, and keeps track of the whereabouts of the mouse, and what state the mouse is in. If the mouse is clicked and the mouse pointer is within the bounds of the control, it tells all other objects/classes that have registered for that event to do what they have been told to do. There is a good tutorial on
MSDN about events and eventhandling[
^].
Hope this helps.