This book will be helpful for academicians, researchers and working professionals engaged in the field of science as well as engineering. It provides basic information related to synthesis of magnetic nanoparticles, several synthesis methods, specific characterizations, their stability and applications in variety of fields. This is an introductory book which is applicable for teaching as well as for research purposes. It covers all the major aspects of magnetic nanoparticle synthesis in an easy, accessible and concise ways. The initial chapters described the types of magnetic particles and magnetism in nanoparticles with their occurrences and behavior in different conditions. Later chapters describe the classical methods of nanoparticles synthesis, specific characterizations, stability, and finally broad applications in various technical fields in an exhaustive tabular format for easy and quick access for the readers to the current research scenario which help them to identify the research gap and novelty in the research directions.