Gluon is a type of elementary particle in the field of particle physics. It acts as the exchange particle, or gauge boson, for the strong force, which is one of the four fundamental forces in nature. Gluons are responsible for holding quarks together to form protons and neutrons, which in turn make up atomic nuclei. Gluons are massless and carry a property called "color charge," which is related to the strong force. They interact with quarks and other gluons, creating a complex web of interactions that govern the behavior of particles within atomic structures. This is essential for understanding the structure of matter in the universe, including elements like hydrogen and helium.