The word atom comes from the Greek word meaning indivisible. The concept of the atom had its foundations in ancient Greece with Leucippe of Milet. In 420 B.C. his disciple Democrite of Abdere had the concept that atoms were particles in perpetual motion and were invisible because of their infinitely small size, indivisible, solid, eternal because they are perfect, surrounded by an empty space, and having an infinite number of shapes. His theory was exceptionally close to reality, being that it was 420B.C.
Today we know that each atom is made up of three parts, a proton, a neutron and an electron. These atoms combine to make compounds. The most basic atoms are called elements and cannot be broken down any more than they already are. There are currently 118 known elements 90 of them occurring naturally and the other 28 are man made. The elements combine in an infinitesimal amount of ways to make up every thing around us.
In a compound, atoms are held together by an energy force called a chemical bond, which is somewhat analogous to a piece of elastic holding two balls together. Of course, the bond does not really consist of a material substance, but like a piece of elastic, it represents a certain amount of potential energy.
To carry the analogy further, when either a piece of stretched elastic or a chemical bond id broken, potential energy is converted to kinetic energy. A chemical bond if apparently an energy relationship between atoms.
As I stated in the beginning of this essay, Atoms are