Why is iron called an magnetic substance​

Exactly in the four elements iron, nickel, cobalt and gadolinium, there is interaction between so-called 'unpaired spins'. This interaction ensures that the magnetic moments of atoms can permanently align parallel to each other. The sum of all these small magnetizations forms the nett magnetization of the material

Explanation:

Exactly in the four elements iron, nickel, cobalt and gadolinium, there is interaction between so-called 'unpaired spins'. This interaction ensures that the magnetic moments of atoms can permanently align parallel to each other. The sum of all these small magnetizations forms the nett magnetization of the material