N-linked glycosylation is a biochemical process where carbohydrates, specifically oligosaccharides, are attached to a nitrogen atom in the amino acid asparagine of a protein. This modification occurs in the endoplasmic reticulum and Golgi apparatus of cells, playing a crucial role in protein folding, stability, and function. This type of glycosylation is essential for many biological processes, including cell signaling and immune responses. N-linked glycoproteins are found in various organisms, from bacteria to humans, and are important for the proper functioning of many enzymes and hormones.