write at least two difference between paramagnetic, diamagnetic and ferromagnetic material.

Ferromagnetic materials are the three metals that are always magnetic, like iron. They can retain a magnetic field in the absence of a magnetic field as long as they were once in contact with a magnetic field. They have a memory when it comes to magnetism.

Paramagetic materials show magnetism in the presence of a magnetic field, but lose their magnetic properties once the external field is removed.

Diamagnetic materials create a magnetic field in opposition to an externally applied magnetic field.