The particle that is negatively charged and orbits the nucleus of an atom is called an electron. Electrons are fundamental subatomic particles that play a significant role in chemical bonding and reactions. They are located in electron shells or energy levels surrounding the nucleus, which contains positively charged protons and neutral neutrons. The arrangement and behavior of electrons determine an atom's chemical properties and its ability to interact with other atoms. Understanding electrons is central to the study of chemistry and atomic theory.