1. A sweet-tasting, water-soluble carbohydrate based on a ring of four or five carbon atoms and one oxygen atom.

An essential structural component of living cells and source of energy for animals which includes simple sugars with small molecules as well as macromolecular substances that are classified according to the number of monosaccharide groups they contain.

2. Saccharides are classified as monosaccharides, disaccharides, trisaccharides, and polysaccharides according to the number of monosaccharide groups composing them.