1. Paramagnetism arising from the contributions of the net magnetic moments of the unpaired electron of the individual atoms to molecules in a paramagnetic substance, because of the tendency to align magnetic moments with an external magnetic field.
2. Paramagnetism in a substance in which atoms or molecules possess a net electronic magnetic moment.

It arises because of the tendency of a magnetic field to orient the electronic magnetic moments parallel to itself.

A magnetic moment refers to a vector associated with a magnet, current loop, particle, etc., whose cross product with the magnetic induction (or alternatively, the magnetic field strength) of a magnetic field is equal to the torque exerted on the system by the field.