The aim of this textbook is to provide an overview of nanophotonics, a discipline which was developed around the turn of the millennium. This unique and rapidly evolving subject area is the result of a collaboration between various scientific communities working on different aspects of light-matter interaction at the nanoscale. These include near-field optics and super-resolution microscopy, photonic crystals, diffractive optics, plasmonics, optoelectronics, synthesis of metallic and semiconductor nanoparticles, two-dimensional materials, and metamaterials. The book is aimed at graduate students with a background in physics, electrical engineering, material science, or chemistry, as well as lecturers and researchers working within these fields.