Lots of people think using a layer mask is only for the advanced Gimp users, fortunately this isn't the case at all. Let me explain you the basic usage of layer mask on a easy to follow step-by-step example.
In this simple tutorial suitable for the Gimp beginners as well, we are going to manipulate a photograph of standing still car to make it look like it's passing by real fast.
Pretty nice looking and simple to create effect, where we turn everything into pixels except the selected part. My car will end up looking like it's trying to escape out of the pixelated background.
