The Wa-Bocho (or Japanese style knife) has one distinct feature different from Western style knives: The Kataba, or beveled blade. What this means is that the outer side of the blade is sharpened with a beveled edge, while the inner side remains flat. While the blade is flat on the inner side, the surface is actually slightly concave (Urasuki), giving it the same effect as perforated knives or knives with hollowed edges. Japanese professional chefs prefer these beveled knives, which facilitate extremely precise cutting and clean food separation from the blade. In Japanese cuisine, many ingredients such as fish and vegetables are served raw, and the aesthetics of these foods has always been a vital factor.
Due to demand, Japanese knife manufacturers also continue to produce Western style knives. Unlike Japanese style knives, which have a single bevel (Kataba), Western style blades have been sharpened on both sides. The most common have symmetrical blades, however, some manufacturers will sharpen one side slightly more than the other side, to mimic single bevel blades.