What do both glycolysis and fermentation have in common?

Both glycolysis and fermentation are anaerobic processes, meaning they do not require oxygen. They both begin with the breakdown of glucose to produce pyruvate, generating a small amount of ATP. Furthermore, fermentation is a way to regenerate NAD+ from NADH, which is necessary for glycolysis to continue under anaerobic conditions. Both pathways are crucial for energy production when oxygen is scarce.