This chapter delves into the diverse chemical and physical environments encountered in materials science. It investigates the phenomena of chemical absorptions, intercalations, substitutions, decorations, heterojunctions, and physical perturbations. By examining the effects of these factors on materials, it uncovers insights into the modification and optimization of material properties for targeted applications. This comprehensive exploration equips researchers and engineers with the knowledge necessary to manipulate and enhance material behavior in specific chemical and physical environments.