This book offers to reader a sound understating of two-dimensional Transition-Metal Dichalcogenides (2D TMDs) materials, detailing their physio-chemical mechanisms and technological applications in various areas such as nanoelectronics and optoelectronics. Moving from their invention to their modern developments, including theoretical approaches, experimental interpretations and their technical applications, the book explores the basic concepts of 2D TMDs. It will be of interest to undergraduate and postgraduate students, researchers and scientists working in the area of 2D TMDs. A key goal of this book provides a sound or clear idea about two-dimensional Transition-Metal Dichalcogenides (2D TMDs) materials by providing their sound background, fabrication approaches including interpretations of the inside physio-chemical mechanism including technological applications in various significant areas such as nanoelectronics, optoelectronics, topological insulators, biomedical.