The Warburg effect refers to the observation that cancer cells often prefer to produce energy through a process called glycolysis, even in the presence of sufficient oxygen. This is different from normal cells, which typically use oxidative phosphorylation for energy production when oxygen is available. The reliance on glycolysis allows cancer cells to rapidly generate energy and produce building blocks for growth. This phenomenon was first identified by the German scientist Otto Warburg in the 1920s. The Warburg effect is significant because it highlights how cancer cells adapt their metabolism to support uncontrolled growth and proliferation, making it a key area of research in cancer biology and treatment strategies.