Nesting is the process of arranging components made of cut plate or wood onto the material sheets in such a manner as to maximize utilization of the material available. The unused portions of scrap are known as wastage. Parts, once placed, are known as nested. Sheets are then typically plasma or CNC cut. As parts are fitted on the basis of fit rather than any logical order, they may be scribed by capable machines or marked by hand to match the cut sheets. For CNC, tool paths are defined to minimize tool changes, using bridges to transverse parts. While some software is capable of nesting rather efficiently, in general some level of manual intervention is required for maximum utilization.