Shotokan Karate has as its crest, a Tiger, surrounded by a circle. This design came about as the result of Master Funakoshi meeting a painter in Tokyo shortly after his arrival, named Hoan Kosugi (1881 - 1964). The irregular appearance of the circle around the Tiger suggests that Hoan Kosugi drew it free hand with one continuous stroke of his brush. As for the kanji found in the upper right hand corner, it is Hoan Kosugi's name.
Hoan also encouraged Master Funakoshi to write the first reference book on the subject of karate-do which was ultimately published by Bukyosha, entitled, Ryukyu Kempo Karate-do.
Remember: "The great virtues of karate are prudence, and humility."