Willard Gibbs was an American scientist born on February 11, 1839, in New Haven, Connecticut. He is best known for his contributions to the fields of thermodynamics and physical chemistry. Gibbs developed the concept of free energy, which helps predict the direction of chemical reactions and the equilibrium state of systems. Gibbs also introduced the Gibbs phase rule, which describes the number of phases in a chemical system at equilibrium. His work laid the foundation for modern statistical mechanics and significantly advanced our understanding of chemical processes, making him a key figure in the development of scientific theory.