Lipidomics is the study of the structure and function of the complete set of lipids (the lipidome) produced in a given cell or organism as well as their interactions with other lipids, proteins, and metabolites. Lipids are hydrophobic or amphipathic molecules. The number of distinct lipid species is estimated to be between 104–105. A multitude of nutritionally and metabolically regulated processes maintain lipid homeostasis in healthy conditions. Defects or alterations in the enzymatic metabolism of lipids may contribute to the pathogenesis of common diseases like Alzheimer’s, atherosclerosis, insulin-resistant diabetes, or cancer.