Starch is a complex carbohydrate, or polysaccharide, formed by the linear and branched linkage of many glucose units. It serves as the primary form of energy storage in the tissues of certain organisms. Structurally, starch granules consist of two main types of glucose polymers: amylose, which is a mostly linear chain, and amylopectin, which has numerous points of branching. These chemical properties allow starch to be efficiently metabolized by biological systems, releasing glucose molecules for use in cellular respiration and providing fundamental energy for life processes. Historically, starch has been utilized in technology for industries ranging from adhesives and thickeners to the manufacture of biodegradable materials.