Panzerfaust or Panzershreck????

Can someone please explain how the Panzerfaust was used against armor. Did it have armor-piercing capability? or was it used to disable tanks by knocking off the treads? Did it have any anti-personnel uses…could it be used to attack infantry in buildings, etc.?

The Panzerfaust used the shaped charge effect ton penetrate armor.
A animated gif to illustrate how the hollow charge works.

for more:

http://www.geocities.com/Augusta/8172/panzerfaust1.htm