Difference between protons neutrons and electrons?

Protons and neutrons are in the nucleus of an atom, whereas electrons are present in orbitals, or shells, outside an atom. Electrons are negatively charged, protons positive, and neutrons have no charge, or are neutral. Protons and neutrons have a relative mass of approx. 1 Atomic Mass Unit (amu), whereas electrons have a relative mass of approx 0.00055 amu.

What? i don’t understand