In
MacOS, the universal way to quit a program.
One of the nice little things about the Mac. There's one way to make any application program quit. Hold down the cloverleaf, aka the Apple key, aka the command key, and at the same time press Q.
Isn't that simple? None of this nonstandard "several different tries of ALT-F4, or Control-X or Control-Z or ALT-X" for windows, or whatever the Linux junkies type in to quit XWindow systems.
Of course there's also the force-quit (it's universal), but that's another story, and the app probably doesn't appreciate it.