Wow, lot of confusion here, lets place some sunrays:
Beob. = Beobachter = Observer
Beobab = does not exist, it's Baobab, a kind of large african tree
FO = forward observer
Beob.Wg = Beobachtungswagen = Observation Post Vehicle
Sonderkraftfahrzeug (SdKfz) = Special Purpose Motor Vehicle, this include every vehicle with tracks or wheels, from tanks to halftracked vehicles and armoured cars modified for special purpose, the differeces between them was the number that followed.
examples:
SdKfz 250 = leichter Schützenpanzerwagen
SdKfz 250/5-I = leichter Beobachtungspanzerwagen
SdKfz 263 = Panzerfunkwagen (8-Rad)
SdKfz 267 = Panzerbefehlswagen Tiger I
for refences see:
http://www.panzerlexikon.de/sdkfz.htm
of course this is in german but if you need help drop me an e-mail
Final note: FO vehicles are better used to call in arty (faster and more accurate)
bye
Sorry i forget this one:
SdKfz 253 = leichter gepanzerter Beobachtungskraftwagen = light armoured Observation Post Vehicle
[ July 13, 2001: Message edited by: Mai Thai ]