This textbook is aimed at both experts and general readers. This is because the authors have made a special effort to approach scientific knowledge in a way that is as simple and understandable as possible, so that the book can be read by readers who do not have specialized knowledge but are interested in learning about the phenomena that occur in the Sun. However, since this book also serves the needs of the university course Introduction to Solar Physics, it includes more specialized knowledge. However, non-experts can read only the text, bypassing the mathematical relationships. Similarly, they can skip the description of plasma in the fourth chapter and perhaps the models of flares in the fifth chapter. The book was designed in such a way as to serve the individuality that exists in learning.