The tools of the trade that have evolved for working wood all derive from the simplest forms: axe, adze, chisel. Within those forms, much variation exists. In terms of function, they may be divided into carving tools and joinery tools. Function is determined by form.
Cross lap joints are a great solution when you want to create clean, continuous lines in a timber frame. The edges of the joint are completely flush, making it almost appear that the timbers are magically connected. To create a cross lap joint, you cut halfway through the width of both timbers that you are connecting , and they slide together into an extremely solid joint.