A neutron is a subatomic particle found in the nucleus of an atom, alongside protons. It carries no electric charge, which allows it to play a crucial role in the stability of atomic nuclei. Neutrons contribute to the mass of an atom and help to bind protons together, overcoming the repulsive forces between positively charged protons. Discovered in 1932 by James Chadwick, neutrons are essential in various nuclear reactions, including fission and fusion. They are also used in neutron scattering experiments to study materials at the atomic level, providing insights into their structure and properties.