Brownian motion is the unpredictable motion of suspended particles in a medium. This motion pattern usually consists of spontaneous variations within a fluid subdomain in the direction of an object, accompanied by a displacement to another subdomain.
The motion was named after the botanist Robert Brown who first described the phenomena in 1827 and saw the pollen of a plant submerged in water through a microscope. Nearly eighty years later, theoretical physicist Albert Einstein published a paper in which he modelled the pollen ‘s motion as being moved by individual water molecules , making one of his first major scientific contributions. The Brownian motion theory served as compelling proof of the presence of atoms and molecules.