The Japanese word Gyuto (牛刀) literally translates to beef sword. The gyuto is the equivalent of the Western chef's knife, and is designed to cut everything: vegetables, meats and fishes. It is made to be used with the push-cut method, lifting the blade between each cutting motion, or with the rocking motion method. It is important that the blade is straight upon impact with the cutting board to avoid damage to the knife edge.
Simply explained, Aogami #2 developed by Hitachi Metals is a steel made from Shirogami #2 in which some chromium and tungsten are added for better durability and corrosion resistance. In addition to that, the higher carbon content of the steel allows for better cutting retention. Objectively, the Aogami #2 is an improvement over the Shirogami #2. For patina lovers, however, Shirogami steel will be more reactive to oxidation and could be an advantage.
Shirogami #2 translates to: Shiro (white) and Gami (Steel) and thus; white steel #2. It is named after the color of the package it was wrapped in at Hitachi Metals. The composition of this steel is very pure and contains almost only iron and carbon (1.05%-1.2%). It is in the hands of very experienced blacksmiths that one realizes the enormous potential of Shirogami #2. The quality of the heat treatment and a lower temperature forging are key elements that can allow Shirogami #2 to compete with and even surpass many modern steels. Try a Shiro #2 blade forged by Tanaka-san, Kisuke Manaka-san or Yoshikane Forge and you will see!