In this listing, you started the clock timer with the SetTimer function. The first argument
that you passed to the SetTimer function is the ID for the clock timer. The second argument
is how often you want to trigger the event. In this case, the clock timer event is
triggered every 1,000 milliseconds, or about every second. The third argument is the
address of an optional callback function that you can specify to bypass the WM_TIMER
event. If you pass NULL for this argument, the WM_TIMER event is placed in the application
message queue.