Panzergrenadier is the name for the German form of "mechanized infantry". However, the meaning has to come to mean more and becomes ever more complicated with official name changes that occur during the war. For the most part, the definition of a panzergrenadier is often pictured as elite German infantry, often equipped with such weapons as the Panzerschreck or MG 42 and given half-tracks to keep up and provide infantry support to the ever faster Panzers as they roll across the battlefield.
However, this definition can also be blurred because as the war dragged on, the German war machine could produce fewer and fewer half-tracks and or trucks for which the Panzergrenadiers to use, thus forcing many units to rely on horse drawn supplies/weapons. Also adding to the confusion was the fact that in order to increase German troop morale, regular infanterie (Infantry) divisions were renamed to panzergrenadier divisions without strictly being trained as such.
Ideally however, a panzergrenadier unit could operate at roughly the same combat effectiveness as a panzer division. Particularly, panzergrenadier divisions were oftentimes used to maintain large defensive positions oftentimes at a heavy cost while waiting for backup infantry.