Studying atoms is important because the Universe revolves around the properties of elements, not necessarily the properties of an electron or proton. For example, let's say you have a bar of gold. You know that bar is made of matter because everything is made of matter. The history of atomic structure and quantum mechanics dates back to the times of Democritus, the man who first proposed that matter is composed of atoms. The study of the structure of an atom gives a great insight into the entire class of chemical reactions, bonds, and their physical properties. Nuclear technologies are used worldwide to meet some of the fundamental needs of modern daily life. These include access to energy and proper medical care, food production, and the management of water resources. For example, the human body is made of a collection of atoms that make up the matter of the human body. They are in different states, the blood is a liquid, the bone is a solid and the air we breathe in and out is a gas. Atoms are then used to create the molecules around us.
