Microorganisms that only grow in the absence of oxygen and are, in fact, poisoned by it. Yeasts, many bacteria and mammalian muscle cells are facultative anaerobes. Can make ATP by fermentation in the absence of oxygen or by respiration in the presence of oxygen. Glycolysis is common to both fermentation and respiration, so pyruvate is a key juncture in catabolism. The first prokaryotes probably produced ATP by glycolysis.
Glycolysis is the most widespread metabolic pathway, so it probably evolved early.
Glycolysis occurs in the cytosol and does not require membrane-bound organelles. Eukaryotic cells with organelles probably evolved about two billion years after prokaryotic cells.