WHY do metallic objects get attracted to a magnet? Is it because of particular charges or what 

Whether a metal will be attracted or repelled by the magnet depends upon the number of unpaired electrons in an atom of the metal. Only those metals which possess unpaired electrons will be attracted a magnet. This is because if there are unpaired electrons, there will be net electron spin that can interact with the magnetic field of the magnet. In case of certain metals which do not possess unpaired electrons, the electron spins of individual electrons cancel each other, with the result that these metals are not attracted by magnetic field produced by a magnet. 

Hope this helps.