Martial arts are codified systems and traditions of combat practiced for a number of reasons such as self-defense; military and law enforcement applications; competition; physical, mental and spiritual development; and entertainment or the preservation of a nation's intangible cultural heritage. Although the term martial art has become associated with the fighting arts of East Asia, it originally referred to the combat systems of Europe as early as the 1550s. The term is derived from Latin and means "arts of Mars", the Roman god of war. Some authors have argued that fighting arts or fighting systems would be more appropriate on the basis that many martial arts were never "martial" in the sense of being used or created by professional warriors.