Please note that the content of this book primarily consists of articles
available from Wikipedia or other free sources online. Skill in the
traditional board game Go is measured by a number of different national,
regional and online ranking and rating systems. Traditionally, go
rankings have been measured using a system of dan and kyu ranks.
Especially in amateur play, these ranks facilitate the handicapping
system, with a difference of one rank roughly corresponding to one free
move at the beginning of the game. This system is also commonly used in
many Asian martial arts, where it often corresponds with a belt color.
With the ready availability of calculators and computers, rating systems
have been introduced. In such systems, a rating is rigorously calculated
on the basis of game results. Traditionally, the level of players has
been defined using kyu and dan ranks. Kyu ranks are considered student
ranks. Dan ranks are considered master ranks. Beginners who have just
learned the rules of the game are usually around 30th kyu.
