Physics 2201 is an introductory course to the ideas and methods of thermal physics. Thermal physics has applications in fields of physics as diverse as cosmology to microbiology, as the interior of a star to or our atmosphere. It is therefore an essential ingredient of any undergraduate physics course. Thermal physics has its historical roots in Classical Thermodynamics and in its modern form as Statistical Mechanics. In this course we will begin with a general review of, or introduction to the thermal properties of macroscopic systems and introduce at an early stage the use of the statistics of large numbers to understand how the microscopic world leads to an understanding of the behavior of large-scale systems. The emphasis will be on seeing how these very basic ideas have applications in many different areas of study.