<Li> Stirrup first few centuries AD </Li> <P> During most of the Paleolithic - the bulk of the Stone Age - all humans had a lifestyle which involved limited tools and few permanent settlements . The first major technologies were tied to survival, hunting, and food preparation . Stone tools and weapons, fire, and clothing were technological developments of major importance during this period . </P> <P> Human ancestors have been using stone and other tools since long before the emergence of Homo sapiens approximately 200,000 years ago . The earliest methods of stone tool making, known as the Oldowan "industry", date back to at least 2.3 million years ago, with the earliest direct evidence of tool usage found in Ethiopia within the Great Rift Valley, dating back to 2.5 million years ago . This era of stone tool use is called the Paleolithic, or "Old stone age", and spans all of human history up to the development of agriculture approximately 12,000 years ago . </P> <P> To make a stone tool, a "core" of hard stone with specific flaking properties (such as flint) was struck with a hammerstone . This flaking produced sharp edges which could be used as tools, primarily in the form of choppers or scrapers . These tools greatly aided the early humans in their hunter - gatherer lifestyle to perform a variety of tasks including butchering carcasses (and breaking bones to get at the marrow); chopping wood; cracking open nuts; skinning an animal for its hide; and even forming other tools out of softer materials such as bone and wood . </P>

When was the first piece of technology invented