Glycolysis
Glycolysis (from Greek glyk meaning sweet and lysis meaning dissolving; also known as the Embden-Meyerhof pathway) is the initial stage of glucose metabolism and converts 1 molecule of glucose into 2 molecules of pyruvate. Glycolysis takes place within the cytosol of the cell and is completely anaerobic; that is, oxygen is not required.

Glycolysis is the only metabolic pathway common to nearly all living organisms, suggesting great antiquity; it may have originated with the first prokaryotes, 3.5 billion years ago or more.