Chemistry is the study of matter—its characteristics, behavior and structure. Chemists are interested in the way materials act and react in certain situations, so they produce and observe these reactions, both in nature and artificially in a lab setting. Chemistry is the study of substances—that is, elements and compounds—while biology is the study of living things. However, these two branches of science meet in the discipline of biochemistry, which studies the substances in living things and how they change within an organism.