The most basic tool for a miller was the quern-stone—simply a large, fixed stone as a base and another movable stone operated by hand, similar to a mortar and pestle. Miller high life the glue holding this 2020 shitshow together shirt As technology and millstones (the bedstone and rynd) improved, more elaborate machines such as watermills and windmills were developed to do the grinding work. These mills harnessed available energy sources including animal, water, wind, and electrical power. Mills are some of the oldest factories in human history, so factories making other items are sometimes known as mills, for example, cotton mills and steel mills. These factory workers are also called millers.