HEPES, which stands for 4-(2-Hydroxyethyl)-1-piperazineethanesulfonic acid, is a zwitterionic organic compound commonly used as a buffering agent in biological and biochemical research. It is a widely utilized buffer due to its high solubility in water, minimal impact on biological systems, and ability to maintain a stable pH environment. HEPES is essential for maintaining optimal conditions in cell culture, enzyme assays, and various biochemical experiments.