The smallest unit of an element is an atom. Atoms are made up of tiny particles called subatomic particles that give atoms their properties and characteristics. It is the study of these properties, combined with techniques, methods and concepts that comprise the backbone of studying the Atomic Structure. Since the atom is central to the study of all Physical Sciences, it is important to establish strong foundational skills that include mastery of types, history and various states of Atomic Structure. This topic will provide mastery of introductory concepts and proficiency in more advanced areas.