What would you say is the best man-made invention throughout the ages? Some might say the electric light or the telephone or perhaps the automobile. But of course, we would argue that the best thing made by man is the cutting edge. The first knife-like tools were made in prehistoric times. These hand tools, or Oldowan, are the oldest known and said to have first appeared 2-3 million years ago. They were made by chipping stones to create a chopping or cutting edge and were typically made from a single "core" stone. These knives were made and used as needed and for hunting purposes and basic survival.