kompressors

Yes, yes, I know they're Mercedes's name for super-chargers. And I know Mercedes started introducing them about 10 years ago. And I know it's made a mess of the nomenclature with a 230K having a 1.8. But why were they introduced? What does a Kompressor do that a bigger engine does not? And why a...

Just wondering if pootling around (wafting as it were) would cause the Kompressor to spin?

if an engine is super/turbocharged - where does the vacuum for the brakes etc come from? the same as diesels? as in a pump on an alternator? im thinking of supercharging the 6.9 (with 5psi or so) - but as the plenum chamber would be above atmospheriuc pressure, things like the vac control...