Decyl Glucoside is a glucose-based surfactant and emulsion stabilizer. It is created by reacting glucose with the fatty acids from plants.

Surfactants help clean the skin by trapping oil, sebum, and dirt to be washed away. As an emulsion stabilizer, it stabilizes the ingredients in a product by preventing them from separating.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.