Suddenly remembering my first encounter with this important distinction via the "mouseUp" event in HyperCard. I remember discovering that it's usually better t

Suddenly remembering my first encounter with this important distinction via the "mouseUp" event in HyperCard. I remember discovering that it's usually better to act on a mouseUp. On mouseDown feels too fast, and if you act on mouseDown you prevent the user from being able to move the cursor away to "cancel" the click. There are probably other reasons I can't recall at the moment, too :)