Cold process soap is a method of making soap without the use of heat. In this technique, oils and fats are combined with a lye solution, which initiates a chemical reaction called saponification. This process transforms the mixture into soap, allowing for the creation of various textures, colors, and scents. The cold process method allows for greater control over the ingredients, making it popular among handmade soap enthusiasts. It typically takes 4 to 6 weeks for the soap to cure and become safe for use, as the lye fully reacts with the oils during this time.