Explain the magnetic properties of solids.

(N/A) Every substance has some magnetic properties associated with it. The origin of these properties lies in the electrons.
Each electron in an atom behaves like a tiny magnet.
Its magnetic moment originates from two types of motions: $(i)$ Orbital motion around the nucleus,$(ii)$ Spin motion around its own axis.
Each electron has a permanent spin and an orbital magnetic moment associated with it.
This magnitude of magnetic moment is very small and is measured in the unit Bohr magneton,denoted as $\mu_{B}$,which is equal to $9.27 \times 10^{-24} \ A \ m^{2}$.