Basically epigenetics describes a procedure that turns our genes on and off. These changes in the expression of genes are caused by certain base pairs in DNA, (or RNA), being "turned off" or "turned on" again, through chemical reactions. The process works by chemical tags, known as epigenetic marks, attaching to DNA and telling a cell to either use or ignore a particular gene. Some epigenetic tags remain in place as genetic information passes from generation to generation, a process called “epigenetic inheritance”.
Recently experts have witnessed evidence of psychological epigenetics in our heritance; through this new viewpoint offspring may inherit altered psychological traits due to their parents past life experiences (and core trauma wounds).