Ethylhexylglycerin (we can't pronounce this either) is commonly used as a preservative and skin softener. It is derived from glyceryl.

You might see Ethylhexylglycerin often paired with other preservatives such as phenoxyethanol. Ethylhexylglycerin has been found to increase the effectiveness of these other preservatives.

Polyglyceryl-3 Methylglucose Distearate is created from the diester of stearic acid and the condensation product of methylglucose and Polyglycerin-3.

As an emulsifier, it is used to bind ingredients together. Many ingredients, such as oils and water, separate naturally. Emulsifiers prevent them from separating to ensure even consistency in texture.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin. 

It’s often used to:

Tromethamine helps balance the pH and improve the texture of a product. It is synthetically created.

As an emulsifier, Tromethamine prevents oil and water ingredients from separating. This helps stabilize the product and elongate a product's shelf life. Tromethamine also makes a product thicker.

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.