Quit apps on Mac
It’s easy to quit an app or to make sure that apps don’t reopen when you restart your Mac.
Tip: You can have several apps open at once—you don’t have to quit apps when you’re done working in them.
Quit an app
While in the app, choose App Name > Quit App in the menu bar. For example, choose Mail > Quit Mail.
Note: When you click the red Close button 
in the top-left corner of an app’s window, the window closes, but the app remains open. See Manage windows.
Set all app windows to close when quitting apps
By default, when you reopen an app, any windows that were open when you quit the app reopen. If you prefer, you can have windows close when you quit apps.
On your Mac, choose Apple menu
Select “Close windows when quitting an app.”
Quit all apps when you restart, shut down, or log out
On your Mac, choose Apple menu
For more ways to restart, shut down, and log out, see Log out, sleep, wake, restart, or shut down your Mac.
In the dialog that appears, deselect “Reopen windows when logging back in.”
If an app doesn’t quit as expected, you can force quit the app (you may lose unsaved changes). Choose Apple menu > Force Quit, select the app in the dialog that appears, then click Force Quit.