DNA is a molecule made up of two chains that coil around each other in order to form a double helix. It carries genetic instruction for the functioning, growth, development and reproduction of all organisms and viruses. The process by which methyl groups are added to the DNA molecule is known as DNA methylation. The process of methylation can change the activity of a DNA segment without impacting the sequence. In human beings, DNA methylation is a vital process for normal development. Various processes like genomic imprinting, X-chromosome inactivation, repression of transposable elements, etc. are also associated with DNA methylation. DNA has four bases out of which two cytosines and adenine can be methylated. This book unravels the recent studies in the field of DNA methylation. From theories to research to practical applications, case studies related to all contemporary topics of relevance to this field have been included herein. Those in search of information to further their knowledge will be greatly assisted by this book.