In graphite, electrons are

In graphite, each carbon is sp²-hybridized where it uses 3 out of its 4 outer energy levels for the covalent bonding with other neighboring C atoms in a plane. There is one electron present in unhybridized p-orbital of C-atom, which does sidewise overlapping to form a $\mathrm{\pi }$-electron cloud, which is delocalized in the entire structure of graphite. This indicates that the electrons are spread out between the structure.