They had different religions, beliefs, ideals, lived in different regions, and etc. Their culture as a whole are different even though certain aspects are similar.
The differences between the Aztec and Inca societies were: -Inca's empire was more vast than the Aztec -The Aztec methods of communication were less advanced -Different locations (Inca - Andes Mountains, Aztec - Mexico Valley) -Different forms of documentation -The Aztec were industrialized whilst the Inca relied on agriculture