Neutrons make up more than half the matter in our everyday world. As its name implies, the neutron is electrically neutral, but the quarks that make up a neutron are charged. Moreover, the distributions of positive and negative quarks inside a neutron are different, which leads to a separation of charge inside the uncharged particle. Precise knowledge of this charge distribution may give important clues about the strong forces that bind quarks together in neutrons, protons and other composite particles.