Windmills are machines that take wind and convert it into energy.  The windmill was made in Persia by Estakhri in the 9th century.  But windmills were first invented to grind grain and pump water it wasn't until later that they produced energy.  Older wind mills are bigger and made of wood, but newer ones are still big but they are made of steel and fiberglass.

Windmills have come along way from when they were first created to now.  Windmills in the earlier days were located on farms, and now because they can turn wind into energy they can be found in all different places.  But they are expensive and take some time to put up.  Windmills have come along way over the years.