Statistical Thermodynamics

Statistical Thermodynamics is a branch of physics that aids in understanding the behaviour of a large number of particles in a system. It unveils how macroscopic properties, like temperature or pressure, emerge from the individual actions and interactions of these particles. By applying statistics, it relates observable phenomena such as heat, to the unseen microscopic world, providing a bridge between the micro and macro realms in terms of energy and its distribution. It's essentially why an ice cube melts in your drink, or why the air in a balloon expands when heated.