Glycerol is a trihydric alcohol (containing three -OH hydroxyl groups) that can combine with up to three fatty acids to form monoglycerides, diglycerides, and triglycerides.
Triglycerides are chemical compounds formed from one molecule of glycerol and three fatty acids.
Diglycerides have two fatty acid radicals.
Monoglycerides have only one fatty acid radical per molecule of glycerol.