Arrow heas are sharpened or flintknapped stones, flakes, and chips of rock that are sharpened enough for the tip of an arrow. Prehistoric peoples often used various stone spear heads and arrow heads for their weapons and hunting tools. A wide variety of prehistoric arrow heads have been found in each region of the world, and there are distinct changes over time. Arrow heads differ from other stone tools in that the only part of the arrow or spear that has survived for thousands of years is the stone tip, or stone arrow head. The arrow head itself was not a tool, and the prehistoric tools of bows, arrows, and spears are not as easy to find.