Glycan arrays are among the technologies of modern glycobiology. Complex carbohydrate structures from oligosaccharides or polysaccharides are immobilized on a support material. Subsequently, it can be tested with potential interaction partners, for example lectins, antibodies, cell surface receptors or possibly an entire organism. Glycan arrays have broad applications ranging from glycan binding protein specificity studies to medical research to identify biomarkers or to support vaccine development. Synthetic and natural glycan structures can be used for screening on glycan arrays.