Chromatin is a complex of macromolecules composed of DNA, RNA, and protein found within the nucleus of eukaryotic cells. The basic structure of a chromatin is known as the nucleosome. One nucleosome consists of 147 base pairs of DNA wrapped around the outside of 8 proteins known as histones. Each of the histones (H2A, H2B, H4, and H3) come together to form a histone octamer. Nucleosomes are then folded to produce the chromatin fiber. Chromatin fibers are coiled and condensed even further in order to form what is known as chromosomes.