The structure of a growth or an etch front on a surface is not only a subject of great interest from the practical point of view but also is of fundamental scientific interest. Very often surfaces are created under non-equilibrium conditions such that the morphology is not always smooth. In addition to a detailed description of the characteristics of random rough surfaces, "Experimental Methods in the Physical Sciences, Volume 37", "Characterization of Amorphous and Crystalline Rough Surface-Principles and Applications" will focus on the basic principles of real and diffraction techniques for quantitative characterization of the rough surfaces. The book thus includes the latest development on the characterization and measurements of a wide variety of rough surfaces. The complementary nature of the real space and diffraction techniques is fully displayed. It includes an accessible description of quantitative characterization of random rough surfaces and growth/etch fronts. It has a detailed description of the principles, experimentation, and limitations of advanced real-space imaging techniques (such as atomic force microscopy) and diffraction techniques (such as light scattering, X-ray diffraction, and electron diffraction). It has characterization of a variety of rough surfaces (e.g., self-affine, mounded, anisotropic, and two-level surfaces) accompanied by quantitative examples to illustrate the essence of the principles. It is an insightful description of how rough surfaces are formed. There is presentation of the most recent examples of the applications of rough surfaces in various areas.