Chemistry is the science of matter and its interactions with energy and itself
(see physics, biology). Because of the diversity of matter, which is mostly in the form of atoms, chemists often study how atoms of different chemical elements interact to form molecules and how molecules interact with each other.
Branches of chemistry
Chemistry typically is divided into several major sub-disciplines. There are also several main cross-disciplinary and more specialized fields of chemistry.
Inorganic chemistry is the study of the properties and reactions of inorganic compounds. The distinction between organic and inorganic disciplines is not absolute and there is much overlap, most importantly in the sub-discipline of organometallic chemistry.
Theoretical chemistry is the study of chemistry via theoretical reasoning (usually within mathematics or physics). In particular the application of quantum mechanics to chemistry is called quantum chemistry. Since the end of the second world war, the development of computers has allowed a systematic development of computational chemistry, which is the art of developing and applying computer codes for solving chemical proplems. Theoretical chemistry has large overlap with molecular physics.