An epigenetic trait is a stably heritable phenotype resulting from changes in a chromosome without alterations in the DNA sequence. Epigenetic mechanisms have a crucial role in regulation of gene activity and expression during development and differentiation or in response to environmental stimuli. Epigenetic research can help explain how cells carrying identical DNA differentiate into different cell types, and how they maintain differentiated cellular states. Epigenetics is thus considered a bridge between genotype and phenotype, a phenomenon that changes the final outcome of a locus or chromosome without changing the underlying DNA sequence. Multiple mechanistic steps lead to the stable heritance of the epigenetic phenotype. The molecular mechanisms of epigenetic phenomena are multiple. In the current work we reviewed recent updates the role of epigenetics and its basic mechanisms in health and disease.