Spectroscopic methods have opened up a new horizon in our knweledge about solid-state materials. Numerous techniques using electromagnetic radiation or charged and neutral particles have been invented and worked out to a high level in order to provide more detailed information on the solids. In this text, new radiation sources like lasers and synchrotrons are discussed. It prvides a description of the linear response together with the basic principles and the technical background for various scattering experiments. Fourier transform spectroscopy, pulsed and magnetic NMR tecniques, photo-emission, and light and electron scattering are elucidated. Each chapter includes problems. The concept of this textbook is designed for graduate students.