This document discusses the different types of carbohydrates. Carbohydrates are composed of carbon, hydrogen, and oxygen and contain a 2:1 ratio of hydrogen to oxygen. There are three main types: monosaccharides (simple sugars like glucose and fructose), disaccharides (formed from two monosaccharides bonded together like sucrose), and polysaccharides (long chains of hundreds of monosaccharides like starch and glycogen). Polysaccharides are insoluble and act as energy stores in plants and animals.