The earliest tools must have been made by cracking or hammering a piece of stones with another stone to improve its shape and extend it for use. These first tools were made by splitting, pebbles were sensibly selected from single-beds and, by a skilful blow or two with another stone, the required sharp edges were produced. Carving on stone and engraving on bones were practiced in an artistic sense of man to reach its highest point. The cave carving were made by man for his shelter. Drawings and paintings of human, animals, notable carvings in horn and engravings on stone made by artists have been discovered by the researchers. The period of Stone sculptors also observed by the construction of countless stone temples, many of which attained considerable size. As vast quantities of sculpture were required to decorate their lavish exteriors and simpler interiors, much of the work is little more than sharp executed architectural ornament. Carving is a difficult process, requiring skill, attentiveness and extreme carefulness. It is a process in which forms are cut away or deducted from the original solid material.