The German Army is called the "Heer"; it is sometimes incorrectly referred to as the" Wehrmacht".
The term "Wermacht" includes all German military forces including Heer (army), Kriegsmarine (navy) and Luftwaffe (airforce)

Germany. Mainly the Wehrmacht. specifically the Heer, and the Luftwaffe. There are Kriegsmarine but they are not common.

at first the wehrmacht isn't the German army the German army is the heer . The wehrmacht is only one of 5( later 6) parts of the heer. They had different coloured uniforms becaus there were many troops different troops like tankpionieres , parahunter and so once... they had different colours that u can recognize them and also they had different uniforms one for fighting ,one for parades ,one for stealth etc.

Rudolf Absolon has written:

'Die Wehrmacht im Dritten Reich' -- subject(s): Germany, Germany. Heer, History