Kado is a skill and performing art which has been passed down in a specific family for generations.
Originally Kado meant morals, household management and a family budget which should be maintained by the family members in a house to manage the family.
Since the Medieval Period among the specific families which had skills and performing arts as their family businesses, people preached the relationships between the family and the professional skill or performing art as their "Michi (way)" by comparing each family's world of the skill or performing art and the values of the back grounds like specialty, universality, tradition, authority and others.
People had been thinking that keeping up and developing a family and the Michi were connected closely; a family existed to pursue the Michi and the Michi was maintained by the family in a complementary relationship. Especially, the tradition inherited from generation to generation and the authority to keep the status and presence as the leader in the field were considered very important. Therefore, to be recognized as a family with Michi, it was not sufficient that each member had the skill and quality but it was also necessary for it to have been continued from generation to generation in a blood relationship or by marriage. But to maintain and inherit such a family it was necessary to practice hard and master the specific "Kata (form)" in the field and the "Kata" was taught orally to one person or only a few people of a generation.
It was possible not to be accepted as the successor if he/she couldn't master the "Kata", even if he/she was someone from the next generation of the blood relationship (Besshikuden of "Fushikaden" written by Zeami)
Since the early-modern times, people and fields blessed with the relationship and philosophy of Family and Michi were expanded more and it was developed to the Iemoto system (a system of licensing inherited by specific families) and philosophies of arts and inherited.