Polysaccharides, the complex carbohydrates made up of repeating units of simpler sugars, have a variety of synonyms. Some common synonyms include glycans, complex sugars, starches, and heteropolysaccharides. Other synonyms include cellulose, which is found in plant cell walls, chitin, which is found in the exoskeletons of arthropods, and hyaluronan, a major component of connective tissues. Polysaccharides also include the well-known molecules such as glycogen, the storage form of glucose in animals, and amylose, a component of starch. However, regardless of their specific names, these macromolecules play an essential role in many biological processes, including energy storage, structural support, and cellular communication.