The term ryu is translated as "school" or "style". For example, when we talk about Wado Ryu style, we mean Wado style karate.
Each school was identified by the surname of its founder (soke) or the founder of a particular 6th style taught in that school; by the name of the clan, under the auspices of which I received official recognition. At the same time, schools were divided into several types: 1) schools in which teaching was conducted by the founders of the 6oe style themselves or their relative students under direct supervision of a mentor; 2) schools run by instructors and teachers who studied with other masters of this style; 3) hereditary ryu - schools that operated under the control of one family of teachers, where the transfer of accumulated experience in the field of djutsu took place directly, from father to son, over the course of many generations; 4) private schools operated 6es of official authorization and did not receive maintenance, because they were ignored by the authorities.