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[edit] The Myth of the "Black" Belt
Myth: Everyone wears white belts to start off. When your belt is dirty enough to look black, you are a black belt.
The kyu/dan ranking system comes from Jigoro Kano sensei (founder of Judo) and had white, brown and black belts. Additional colours were added later on.
Belts should be washed when they are dirty.
However, many dojo follow a tradition wherein the belt is never washed.
