HII galaxies in 4D
  HII galaxies are clumpy and their gas kinematics can be mapped to show the
global turbulent motions and the effect of massive star evolution. The
distribution of their physical conditions is homogeneous and oxygen abundance
is uniform. The presence of nebular HeII 4868 line seems to be higher in a low
abundance galaxy, implying a harder ionization power probably due to stars in
low metallicity. Innovative methods of data cube analysis, namely PCA
tomography (nicknamed 4D), seem promising in revealing additional information
not detected with the standard methods. I review some of our own recent work on
the 3D spectroscopy of HII galaxies.
