Few Table spaces are unlimited

Hello All,

I have one query about table space is unlimeited .

How we can make table space unlimited ? what is the meaning unlimited ? can we extend table space which is showing unlimited ?

PSAPBIWCZOA                      296.140.800      6.050.304         97        130     16.692    Unlimited

PSAPBIWHROA                      466.944.000     74.322.560         84        130     20.776    Unlimited

PSAPBIWODS                       340.971.520     63.085.248         81      1.272     56.155    Unlimited

Thanks