Cholesterol (Chol) is a lipid in the body. It is a part of cell membranes as well as a precursor for vitamin D, steroids, and bile acids. Cholesterol is primarily synthesized in the liver and intestines and is transported via lipoproteins. There are multiple types of lipoproteins, each have slightly different functions. The two most common types of lipoproteins are high-density lipoprotein (HDL) and low-density lipoprotein (LDL).