In thermodynamics, the critical point is the end point of a phase equilibrium curve, where the distinction between liquid and gas phases disappears. At this point, known as the critical temperature and pressure, properties of the substance change dramatically. Beyond the critical point, a substance exists as a supercritical fluid, exhibiting properties of both liquids and gases, which can be useful in processes like extraction and chemical reactions. Understanding the critical point aids in various applications, including material science and engineering, where control over phase behavior is essential.