ELI5: Explain Like I'm 5

Thermal physics

Thermal physics is the study of how energy moves from one place to another in the form of heat. Heat is a type of energy that we can feel when it moves from something that is hot to something that is colder. When two objects are different temperatures, heat will move from the hotter object to the colder one until they reach the same temperature. This is what scientists study in thermal physics.