What is the evolutionary significance of glycolysis?

Glycolysis is one of the oldest and most conserved metabolic pathways, present in nearly all living organisms. Its evolutionary significance lies in its role as an ancient energy-production mechanism that does not require oxygen. This allows glycolysis to have been a primary energy source in early life forms, and it remains crucial today for both prokaryotic and eukaryotic organisms. It provides ATP and intermediates for other biosynthetic processes.