Quick Mask is a tool which is comparatively easy and a time saver. With this tool, you are allowed to paint an inverse selection using brush, paint bucket, or pencil etc; shades of black and grey backgrounds are used. You would notice that when you paint the background, the area starts turning pink in colour. This pink area marks the masked area. You can switch back to normal mode, when all of the background has been painted pink; you would see that clear parts of Quick mask have been selected, for any changes that you might like to apply. You can then inverse the selection and press delete to delete the background.
