Carbohydrates are the most important bioinformational molecules in the cell. The reason for the functional diversity of plant and animal cells is their glycosylation. Glycans are not synthesized based on nucleic acid templates. They are synthesized through enzymatic systems. As a result of protein glyco-sylation, part of the obtained glycoconjugates remains linked to the cell membrane. Any other structure that approaches the cell first comes into contact with these glycoconjugates. Glycans ensure essential communication between cells of a single organism. Glycans constitute the main component of prote-oglycans and the glycocalyx. The entire surface of any cell is covered with glycoconjugates. Therefore, they cause a functional diversity of the cell. Fully assessing the role of glycans in the functional diversity of living organisms is an extremely difficult task and requires long-term and serious research.