Carbohydrates are a large group of organic compounds consisting of carbon, hydrogen, and oxygen which can be typically broken down into monomers to release energy in living beings. Carbohydrates are a class of naturally occurring compounds, probably the most abundant and widespread organic substances in nature. They are essential constituents of all living things. Learn how carbohydrates are composed of carbon, hydrogen, and oxygen atoms and how they vary in complexity and structure. Explore the types, properties, and functions of simple and complex carbohydrates , such as sugars, starches, and fibers. This article explores the structure of carbohydrates and its types, focusing on their major classifications and how their structures inform their roles in living systems.