Exiting from Mail

  Choose Exit from the main window's File menu to close the
  main window and any open Read or Create-Send windows.

  The Exit menu item is available on the File menu when there
  is only one main window open; if multiple main windows are
  open, the File menu contains the Close menu item instead.

  Open folders and drawers are closed.  Wastebaskets are
  emptied, if specified in your Mail User options.  If you have
  made any changes to your user profile, Mail asks whether
  you want to save them.

  Additional topics:

  *   Overview of Mail