you need to know vbscript  really and xml, xsl too. The VB script can take
hold of the sps dll's (basically CDO) so you can query sps and perform
operations using that. I guess you can do SQL/ADO server DB stuff too but I
haven't personally done that yet. Maybe someone else has on here?
API is much more low level that SPS - SPS is basically asp  technology I
suppose. API is really for the OS not for packages themselves (although it
is possible that SPS may have some API calls to various windows routines -
but I don't think it does).