Genetics is a field of science that is concerned with the study of genes, variation and heredity. It also involves the medical practice of diagnosing, treating and counseling patients with genetic disorders. Genetics overlaps with many other areas such as biotechnology, agriculture and medicine. Modern genetics focuses on the function and behavior of genes, gene structure and distribution from the context of cell and organism with respect to a population. Genetic processes interact with two factors - the environment and experiences of the organism. This influences the organism's behavior and development. Genetics is an upcoming field of science that has undergone rapid development over the past few decades. This book is a compilation of chapters that discuss the most vital concepts and emerging trends in the fields of plant and animal genetics. It will help the readers in keeping pace with the rapid changes in this field.