Germany introduced postal codes on 25 July 1941, in the form of a two-digit system that was applied initially for the parcel service and later for all mail deliveries. This system was replaced in 1962 in West Germany by a four-digit system; three years later East Germany followed with its own four-digit system. Whereas the Federal Republic introduced a system with space left for the East German postal system after a possible reunification, such as by omitting all codes starting with '1' and '9', the German Democratic Republic had a system that used all codes starting from '1' to '9' just for East Germany.