Proton
Protons are one of the two types of sub-atomic particles that form in the nucleus of an atom (together with neutrons).[1]. Proton, a term which originates from the greek "protos", meaning "first", is a positively charged particle that exemplifies the theory of containement, and is one that exists due to the mediation of the strong nuclear force by gluons and electrons. Protons also exert an electrostatic attraction to electrons, leading of course to the presence of orbitals, shells and electron promotion in the d-block (a property which makes transitional compounds colored).
A proton is made up of two up quarks and one down quark. According to the Standard Model of particle physics, quarks are fundamental particles, meaning that they cannot be split into smaller particles.[2]