What is a slicer knife used for, i just ordered the wusthof grand prix 2 8 piece set and this knife?

Slicer knife is used to cleanly slice peaces of meat and other soft food, often large. Because of that 6in long slicer sounds more like a joke.
The idea of the slicer knife is to cut the piece in one (or two at most) slicing motion in order to have a cleanly cut surface on the slice.
Obviously with 6 incher you can’t do that and you’ll get jagged cuts.
I’ve looked that set up and it’s more like utility knife than a slicer.
Here’s what real slicer should look like – http://zknives.com/knives/kitchen/ktknv/watanabe/watanabesj300.shtml
http://zknives.com/knives/kitchen/ktknv/watanabe/watanabesjka300.shtml

As for the utility knives, they’re one of the the most useless kitchen knives. Too short and no knuckle clearance, to be useful for veggie chopping like chaf’s knives or vegetable cleavers or nakiris.
Too long to be as good as paring knives for peeling/paring.

Slicers don’t work well as serrated bread knives, but vice-versa works better.
Carving knives are yet another type.