The book "Nonlinear Excitations in NIMs and other materials" by Vivek Kumar Sharma offers a comprehensive investigation of modulational instability and soliton-like solutions for various structures of the nonlinear Schrödinger equation (NLSE). It highlights the properties of materials with a negative refractive index (NIMs) and analyzes the soliton-like solutions for higher orders of the NLSE as well as for coupled modes. Special attention is given to the study of modulational instability in twin-core fibers, a physical system of significant interest that is responsible for generating soliton pulses in various nonlinear media. Furthermore, the soliton-like solutions for the higher nonlinear Schrödinger equation (HNLSE) in ordinary nonlinear materials are addressed, and the effects of the source term on modulational instability in the NLSE with a source are discussed.