"Soap-less soaps" are generally referred to as non-soap cleansers. They differ from regular soap in that they contain synthetic materials rather than the fats or oils used in true soap. In true soap, a fat or an oil (often derived from animal products) is combined with an alkali (like salt) to create a chemical reaction. The soap breaks the surface tension of water and helps bind dirt and grim to that water so you can wash clean. Some soaps can be caustic, which means they slightly corrode the top layer of skin or fabric. A non-soap cleanser performs the same cleaning function but with a synthetic, chemically generated reaction rather than the natural reaction of true soap. Non-soap cleansers are often recommended for people with dry skin or certain skin conditions. One common non-soap cleanser is Cetaphil. This is generally recommended as a face wash or body wash for those with acne or eczema. Of course, there are many different brands and types of non-soap cleansers.