Helium atom. Diagram of an atom of the element helium, showing the central nucleus surrounded by its electron orbital. - Stock-Video

Helium is the second element, and has two protons (red) in its nucleus, along with two neutrons (blue). Helium has two electrons, which occupy the lowest energy 1s orbital (green sphere). Each orbital can hold two electrons, so this 1s orbital is full. For clarity, a solid line shows the paths of the electrons. In reality, electrons can be found anywhere, and the shapes of orbitals are based only on where they are most likely to be found