Genetic information resides in the genome, however, it does not explain how the genome is interpreted. In the 1940s, a new area of research called epigenetics emerged, and since then, extensive efforts have been made to understand the molecular mechanisms underlying these processes began. This has led to the identification of DNA methylation, histone modifications, histone variants, chromatin looping, 3D chromatin conformation, specific positioning of the DNA within the nucleus, and non-coding RNAs. While the DNA sequence remains constant, the epigenome varies from cell to cell and can also change throughout an individual’s life, for example, in response to environmental stimuli. It is interesting to note that many unhealthy lifestyles or pathological conditions exhibit variations in the epigenome, opening up possibilities for intervention.