An Introduction to Thermal Physics is a foundational book that presents the principles of heat, energy, and temperature in a clear, coherent, and conceptually rich manner. Designed for students and general readers with an interest in physics, the book serves as a gateway to understanding how thermal phenomena govern both everyday experiences and advanced scientific systems. It brings together the classical ideas of thermodynamics and the microscopic insights of statistical mechanics to offer a unified view of thermal behaviour in nature. The book begins by introducing the basic concepts of temperature, heat, work, and internal energy, establishing the language and framework needed to explore thermal systems. It then develops the laws of thermodynamics in a logical progression, explaining their physical meaning and practical significance. Special attention is given to thermal equilibrium, energy conservation, and entropy, helping readers grasp not only how thermal processes occur but also why they proceed in a particular direction. A key strength of An Introduction to Thermal Physics lies in its balanced approach between theory and application. Abstract concepts are consistently connected to real-world examples, such as engines, refrigerators, phase transitions, and heat transfer processes. The book also introduces the statistical interpretation of thermodynamics, showing how macroscopic laws emerge from the collective behaviour of microscopic particles. This perspective deepens conceptual understanding and prepares readers for more advanced studies in physics. Written in an accessible and structured style, the book emphasizes clarity without oversimplification. Mathematical treatments are presented carefully to support physical insight rather than obscure it.