Abstract
Whereas DNA, RNA, and proteins are linear polymers that can usually be directly sequenced, glycans show substantially more complexity, having branching and anomeric configurations (alpha and beta linkages). The biosynthesis of glycans, termed glycosylation, is extremely complex, is not template-driven, varies among different cell types, and cannot be easily predicted from simple rules. This overview discusses the stereochemistry of monosaccharides and glycans and provides diagrammatic representations of monosaccharides (Fisher projections and Haworth representations) and formulas for representation of glycan chains. A glossary of terms used in glycobiology is also provided.