* Protons are positively charged particles. The number of protons determines the element of the atom.

* Neutrons are neutral particles, meaning they have no charge. They contribute to the atom's mass but not its charge.

Together, protons and neutrons are called nucleons, and they are held together by the strong nuclear force. This force is incredibly strong, much stronger than the electromagnetic force that repels protons due to their positive charges.

It's important to note that the nucleus is very small compared to the overall size of an atom. Most of the atom's volume is empty space, where electrons orbit the nucleus.