Epigenetic markers are chemical modifications that occur on DNA and histone proteins, affecting gene expression without altering the DNA sequence. These markers include DNA methylation, histone modification, and RNA-associated silencing. Epigenetic markers play a vital role in various biological processes, such as development, cellular differentiation, and the response to environmental factors. Epigenetic markers are heritable through cell division, allowing cells to remember their gene expression state. However, they can also be influenced by external factors like diet, stress, and exposure to chemicals, leading to changes in gene expression patterns. This dynamic nature of epigenetics bridges the gap between genetics and environmental influences on organismal and cellular function, offering insights into complex diseases, aging, and evolution.