Bronchopneumonia is spread throughout the lungs, atypical or interstitial pneumonia happens interstitium around the alveoli, and lobar pneumonia usually infects an entire lobe of the lung.
And in a lobar pneumonia, the infection causes complete consolidation of a whole lobe of the lung, meaning that the entire region is filled with fluid.
You might have a lobar pneumonia, for example, and they could give you an antiserum, an injection of rabid antibodies to the bacterium streptococcus, if the intern sub-typed it correctly.