Cyclopentasiloxane, or D5, is a silicone used to improve texture of products and trap moisture.

D5 is considered lightweight and volatile. Volatile means it evaporates quickly after application. Once evaporated, D5 leaves a thin barrier that helps keep skin hydrated.

Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.

It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.

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.