In choosing the best kitchen Japanese knife you should pay particular attention to the type of steel used in the blade.  Steel is really the essence of the blade and primarily responsible for how the knife performs.  Steel is essentially an alloy (i.e. a mix) of carbon and iron that is often enriched with other elements such as nickel to improve certain characteristics depending on the desired application.

In the knife industry different types of steel are created by varying the types of additive elements as well as how the blade is rolled and heated (i.e. the finishing process). Refer to our Knife Steel Composition Chart for more details on these elements.
To understand the process of making traditional Japanese knifes, read this article.

Ultimately, the different types of steel used in knife blades each exhibit varying degrees of these five key properties: