Superconductivity, the remarkable phenomenon of zero electrical resistance and expulsion of magnetic fields in certain materials at low temperatures, has captivated scientists and engineers since its discovery in 1911. This book aims to provide a comprehensive yet accessible exploration of superconductivity, covering its historical development, theoretical foundations, material properties, experimental techniques, and diverse applications. This book is structured to guide readers from the basic concepts to the forefront of current research. We begin with an introduction to the fundamental principles of superconductivity, followed by an examination of the various types of superconductors and their properties. Subsequent chapters delve into the experimental methods used to study superconductors and the practical applications that leverage their unique capabilities. Finally, we explore ongoing research efforts and future directions, highlighting the challenges and opportunities thatlie ahead.