2.21. Quit
The Quit command causes GIMP to close all images and exit. If there are any open images which contain unsaved changes (that is, they are not marked as “clean”), GIMP notifies you and displays a list of the unsaved images. You can then choose which images you would like to save, or you can cancel the command. Note that if you have a large number of images open, or are using a large part of the RAM on your system, it may take a little while for everything to shut down.
2.21.1. Activate Command
You can access this command from the image menubar through File → Quit,
or by using the keyboard shortcut Ctrl+Q.
For most systems on which the GIMP runs, you can also execute it by clicking on a “Close” button somewhere on the main image window’s titlebar. The location and appearance of this button are determined by the windowing system and the window manager. Clicking on this button closes GIMP when no image is open.