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<h3>Why messages <i>and</i> notifications?</h3>
<p>Basically, a message may have a return value, and is usually thought as a query. A notification simply informs of some event, and is more usually thought as a command. However, a notification is brought by a Windows message, WM_NOTIFY.
</p><p>While the meaning of the two parameters a message can carry – known as wParam and lParam – depend on the message, things are much clearer for a notification. The WM_NOTIFY message holds