What is ferromagnetic and paramagnetic

Ferromagnetic materials are strongly attracted to magnetic fields and can retain their magnetism even after the external magnetic field is removed, becoming permanent magnets. This is due to the presence of magnetic domains that align in the presence of an external field. Examples include iron, nickel, and cobalt.

Paramagnetic materials are weakly attracted to magnetic fields but do not retain their magnetism once the external field is removed. They contain unpaired electrons whose magnetic moments align randomly in the absence of an external field, but partially align with an applied magnetic field. Examples include aluminum, platinum, and oxygen.