Windmills are structures that convert wind power into rotational energy. This energy is applied to grind grain, pump water, or generate electricity. Windmills are generally oriented vertically, but through history some horizontal designed windmills are documented. The vanes of the windmill are called sails or blades and are covered with a satin cloth or wooden shutters. Most windmills have four sails, but designs with as many as eight sails can be found. In the Netherlands the positions of the sails in non-working windmills, can signal joy or mourning. Our Windmill pattern set contains designs created from photographs of windmills in various environments including clear and cloudy skies, grassy fields, along water ways and roads, and with sunrises in the background.