The order of phase transitions can be determined by analyzing the continuity of the Gibbs function. A first-order transition occurs when the Gibbs function is continuous, but its slope is discontinuous, indicating latent heat, such as in melting. In contrast, a second-order transition is characterized by both the Gibbs function and its first derivative being continuous, while the second derivative is discontinuous. The conductor-superconductor transition in liquid helium is noted as a known example of a second-order transition. Recent developments in thermodynamics have expanded the understanding of phase transitions, including concepts like the 'lambda transition' and renormalization.