What shall we call it?
Michael Faraday got the term diamagnetism from William Whewell.
A ferromagnetic material can be permanently magnetized;
it can have its own persistent magnetic field.
Diamagnetic and paramagnetic materials get only temporary magnetic fields
induced by other magnetic fields.
The induced magnetic field in a diamagnetic material is in the opposite direction,
so an exterior magnetic field repels it.
The induced magnetic field in a paramagnetic material is in the same direction,
so an exterior magnetic field attracts it.
See also in The book of science:
Readings on wikipedia: