The book aims to explain the basic ideas of thermal physics intuitively and in the simplest possible way. It is aimed at making the reader feel comfortable with the ideas of entropy and free energy. Thermal physics is prone to misunderstanding, confusion and is often being overlooked. However, a good foundation is necessary to prepare the reader for advanced level studies.

This book is an informal, readable introduction to the basic ideas of thermal physics. It is aimed at making the reader feel comfortable with the extremum principles of entropy and free energies. There is a repeating theme: Molecules (spins) do X to maximize their entropy, and molecules (spins) do XX to minimize their free energy. This finally leads to the idea of the Landau-Ginzburg free energy functional. The author illustrates how powerful the idea is by using two examples from phase transitions.