Japanese Saws come in 3 main types: Dosuki, Ryoba and Kataba.
Dozuki: In Japanese Dozuki means "attached trunk" and refers to the stiff rib or spline that supports the blade. Blades on these saws are super thin and can be as thin as 0.3 mm or 0.011". These saws are designed for crosscutting and can produce very precise and smooth cuts. These saws have backs or splines to keep the super thin blade in tension. These saws are the easiest to control, but the spline limits the overall depth of cut.
Ryoba: The Japanese word Ryoba means "double or both edge". These saws have teeth on both sides of the blade. One side has coarse teeth and is designed for ripping while the other side has finer teeth and is designed for crosscutting. These saws have thicker blades, are much sturdier and allow deep cuts.
Kataba: In Japanese Kataba means "single edge". These saws have teeth on just one side of the blade and do not have backs or splines. These saws can have teeth specifically designed for ripping, crosscutting or angle cutting. These saws have thicker blades and no backs or splines, so they excel at making deep and long cuts.