Joseph Black was an 18th-century Scottish chemist and physician, best known for his work in the field of thermodynamics and chemistry. He discovered the concept of latent heat, which explains how heat is absorbed or released during phase changes, such as when ice melts into water. His research laid the groundwork for future studies in heat and energy. In addition to his contributions to thermodynamics, Black also played a significant role in the development of modern chemistry. He was a mentor to notable scientists like Joseph Priestley and James Watt, influencing their work in gas chemistry and steam engine technology.