[GRASS-user] understanding r.watershed

[Georg Kaspar]

Hi,
when providing a binary depression layer for r.watershed, areas around
those depressions will be left out in the resulting basin map. Are
those areas the watersheds of the given depressions?
According to Markus Neteler's book "Open Source GIS", r.watershed
"does not require filling of depressions in DEM prior to it's
application [...]". What will be the difference if I use a
depressionless DEM (with/without binary depression layer)?
Thank's for your help. I'm new to this field so please excuse any
missing base knowledge!
Best regards,
Georg Kaspar