The name Oldowan (OLD-oh-wan) is derived from the name of the Olduvai Gorge, in northern Tanzania, where crude stone tools, essentially broken river cobbles, were found in association with hominid remains now identified as a distinct species, Homo habilis, and believed to be ancestral to later Homo erectus/ergaster and Homo sapiens forms. The Oldowan toolkit contains a range of core tools (classified as spheroids, discoids, choppers, &c. according to their shapes), and slightly retouched chips, although perhaps the all-purpose "chopper" is most widely thought most representative.
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The extreme crudeness of most Oldowan choppers has two troublesome results. First, it complicates the project of deciding what is or what is not actually a tool, since pebbles and other stones can be broken unintentionally by various natural forces (such a rapidly rushing river banging them together). Second, it invites the extension of the term to cover pretty much any broken pebble anywhere, even in contexts with little imaginable connection to Olduvai or even to Homo habilis or late Australopithenes.
The Oldowan is considered to give way to the later, and also widespread, Acheulean tool kit, associated with Homo erectus/ergaster.
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