The simplest type of carbohydrate is monosaccharides. These are the most basic form of carbohydrates, consisting of single sugar molecules such as glucose, fructose, and galactose. Monosaccharides serve as the building blocks for more complex carbohydrates like disaccharides and polysaccharides. They are crucial for energy production in living organisms, readily absorbed and utilized in metabolic processes. Their structure usually includes carbon, hydrogen, and oxygen atoms, typically in a ratio of 1:2:1.