Wind power has been used for hundreds of years to grind grain, pump water for livestock and now use for electricity. Wind is the movement of air from an area of high surface pressure to an area of low pressure. The sun unevenly heats the earth and therefore wind exists. As long as the sun shines, the wind will continue to blow. When the wind blows, people will take that kinetic energy and convert it into electrical energy and use it in their lives. There are three types of wind systems including grid-tie, grid-tie with battery backup, and off-grid.