The steel on a Japanese knife decides how sharp it gets, how long it stays sharp, and how much babysitting it needs. Here is a plain-language guide to Shirogami, Aogami, VG-10, and the powdered stainless steels, plus what HRC hardness actually means for you.
Four Japanese kitchen knives cover almost everything a home cook does, but they are not interchangeable. Here is what each one is built for, the blade lengths worth owning, and how to pick the first one or two without wasting money on a block set.
A whetstone is the only thing that truly sharpens a Japanese knife, and the basics are simpler than the internet makes them look. Here is how to choose grits, find and hold the angle, raise and chase a burr, and finish a clean edge without grinding your blade away.