Potassium hydroxide, often referred to as caustic potash, is an inorganic compound with the formula KOH. Historically, it was derived from the ashes of hardwood trees and plants, leading to its alternative name, 'lye' or 'potash lye'. This alkaline substance has been used for centuries, primarily in the soap-making process, where it converts fats and oils into soap through a process called saponification. Chemically, it is a strong base, known for its hygroscopic properties, meaning it readily absorbs moisture from the environment. From a holistic perspective, potassium hydroxide, as a base, can symbolize transformation due to its ability to change organic materials like oils into something completely different, like soap. For skin benefits, while pure potassium hydroxide is corrosive and can be harmful, when used correctly in soap-making, it allows for the production of softer, liquid soaps that can be beneficial for the skin. At the end of the soap-making process, there are no traces of potassium hydroxide left when done properly. The resultant soap cleanses effectively, and, depending on the oils used, can offer various moisturizing and nourishing properties.