Chapter 5 discusses endogenic processes that occur beneath the Earth's surface, focusing on magma formation, types of magma, and the principles of rock deformation. It explains how magma forms through processes like decompression melting, heat transfer, and flux melting, and outlines the characteristics of different magma types (felsic, intermediate, mafic, and ultramafic). The chapter also covers rock deformation, stressing the role of differential stress, strain, and the types of faults and folds that result from tectonic forces.