Aztec or Nahuatl writing is a pictographic and ideographic pre-Columbian writing system with significant number of logograms and syllabic signs which was used in central Mexico by the Nahua people. The majority of the Aztec codices were burned either by Aztec tlatoani (emperors), or by Spanish clergy following the conquest of Mesoamerica. Remaining Aztec codices such as Codex Mendoza, Codex Borbonicus, and Codex Osuna were written on deer hide and plant fiber.