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.
Let me show you how to achieve that Depth Of Field effect known from the photography using Gimp. With other words, how to make selected area of the photo sharp and the rest out of focus.
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.
Simple yet very useful Gimp tutorial where we make a detail or an object in a Photo bigger and more visible by resizing it and adding a white rounded square frame around it.