-that is capable of processing the events sent to a window. By default,
-the window is its own event handler, but an application may wish to
-substitute another, for example to allow central implementation of
-event-handling for a variety of different window classes.
+that is capable of processing the events sent to a window. (In other
+words, is able to dispatch the events to handler function.) By
+default, the window is its own event handler, but an application may
+wish to substitute another, for example to allow central
+implementation of event-handling for a variety of different window
+classes.