A katana is consist of various parts, and let's see the most basic parts in this article for a beginner.
The handle of the katana is made of wood we call Tsuka, you'll hold it at the top next to the guard.
The handle wrapping is commonly referred to as Tsuka-Ito, it is made of premium cotton or silk and comes in different colours.
The inside is ray skin and normally in white colour which guarantees a very good grip. And you can also see the two little bamboo pegs that are used to help secure the handle is called mekugi.
The guard we talked about above is called the Tsuba, it can be made of iron, alloys, brass and copper, etc.
The Habaki is a piece of metal encircling the base of the blade which is used to lock the tsuba in place and to maintain the blade in its saya.
The katana scabbard can hold the blade inside safely and keep it as fresh as possible, the Japanese name is called Saya. Saya is normally manufactured from very lightweight wood, with a coat of lacquer on the exterior, and it can also be made from very precious wood or metal.
The rope on the Saya is called Sageo, Sageo is a cord that was traditionally used to secure the scabbard of a Katana to the belt of the person who will wield it.
The most important part of a katana is the blade, how much does a katana blade cost depends on lost factors like the materials, swordsmith skills, time of forging, etc. The material of custom blades could include Maru ( T10 Steel Clay Tempered, Damascus Steel, Damascus Steel Clay Tempered and Wootz Steel Clay Tempered), Honsanmai (Hagane steel for the sword's edge, Shingane steel for the core and Kawagane steel for the exterior of blades), Gomai ( Hagane + Shingane ), Soshu Kitae ( Hagane + Kawagane + Shingane) and Kobuse.