Sometimes the resulting composite image is photographed so that a final image fatheads, and in casual usage is often called "photoshopping" (from the name of the most popular software).
Sometimes the resulting composite image is photographed so that a final image may appear as a seamless photographic print. This latter technique is referred to by professionals as "compositing", and in casual usage is often called "photoshopping" (from the name of the most popular software).