Humans are pretty creative. We adapt the world around us to fit our needs and develop tools to help with almost any task imaginable. Other animals use tools as well, but not to the same extent, and not with the same flexibility and ease.
Tools make us more efficient, and more intelligent (for the most part); they help optimize the relationship between our bodies, our minds, and the world we live in. Some researchers (Clark and Chalmers, 1998; Hutchins, 1995) even argue that tools, in some ways, extend our minds and our bodies. And, in fact, there’s some evidence from cognitive neuroscience that the brain considers tools – at least some of the time – part of the body.