Oldowan Tools
The first stone inventions, Oldowan tools, date back 2.5 million years and consisted of stone "choppers." Our prehistoric ancestors shaped stones into sharp cutting-hammering-digging-scavenging all-in-one tools by breaking off stone flakes. Some of the flakes were also used for digging and scraping purposes.
Acheulean Tools
Acheulean tools were developed 1.5 million years ago, making Oldowan choppers obsolete. The main stone tool invented during this time was the hand ax. This was also a stone-core all-in-one tool, but much more finely shaped and sharpened. Most specimens resemble giant arrowheads. Hand axes were sometimes used for hunting. Stone flakes were also sometimes used as picks or scrapers.
Levallois Tools
One of the most significant stone innovations occurred 200,000 years ago when the focus shifted from the stone core to the stone flake. Prehistoric humans began preparing the cores so that stone flakes of various designs could be cut from them. They would then trim the flakes, making efficient specialty tools, each designed for a specific hunting or gathering task.