The document discusses various types of carboxylic acids including monocarboxylic acids containing one carboxyl group, dicarboxylic acids containing two carboxyl groups, and tricarboxylic acids containing three carboxyl groups. Examples are provided for each type. The document also discusses several saturated fatty acids found in nature including lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, and linoleic acid. Their chemical formulas, structures, sources, and uses are described.