Everything we see is made up of tiny little parts called atoms. The atoms are made of even smaller parts. These are called protons, electrons and neutrons. They are very different from each other in many ways. One way they are different is their "charge." Protons have a positive charge. Electrons have a negative charge. Neutrons have no charge. If two things have different charges, they attract, or pull towards each other. If two things have the same charge, they repel, or push away from each other.
