Liquid soap is a type of soap that is formulated using glycerol, which is also known as glycerin or glycerine. Glycerol is a natural byproduct of the soap-making process and is used as a humectant, meaning it helps to retain moisture in the skin. Liquid soap that contains glycerol can be particularly beneficial for people with dry or sensitive skin, as it can help to soothe and hydrate the skin while also providing cleansing benefits. Glycerol is a safe and commonly used ingredient in many personal care products, including soaps, lotions, and creams.