The human lineage is unique in the animal world for having an adaptation that is based upon the complex use of tools and technology. The archeological record bears testament to the origins and development of technology through time in tandem with major changes in biological evolution. By definition, the archeological record starts as soon as we can identify intentionally or unintentionally modified materials (artifacts) made by humans or protohumans (early hominids) in the prehistoric record. Over the last century and a half, the dates for the origins of the earliest stone tools have been pushed further and further back, as fieldwork intensified in the Old World and dating techniques became more refined.