All matter consists of atoms. Atoms contain three types of smaller particles: protons, neutrons and electrons. Of these three, both the protons and electrons are charged.
Protons are positively charged. Electrons are negatively charged.
Objects that are charged can affect other charged objects using the non-contact forces of static electricity.
Generally, the atom has a neutral charge, but if it loses an electron, it becomes positively charged and if the atom gains an electron, it becomes negatively charged. Charged atoms are called 'ions'.