When you’re finished editing an image, you can close it by clicking the Close button in the upper-right corner (upper-left corner for Macs) of the image. Or, you can choose File→Close or press Ctrl+W (z+W for Mac users) on the keyboard.
If you try to close a file that has been modified since it was last saved, a dialog box will appear, prompting you to save (see Figure 3-19). Click Don’t Save to close the image without saving the changes; click Save to save the changes and close the image; or click Cancel to cancel the entire close operation.
Figure 3-19: This dialog box appears, prompting you to save changes.