A knife is a tool or weapon with a cutting edge or blade, usually attached to a handle or hilt. One of the earliest tools used by humanity, knives appeared at least 2.5 million years ago, as evidenced by the Oldowan tools. Originally made of wood, bone, and stone, over the centuries, in step with improvements in both metallurgy and manufacturing, knife blades have been made from copper, bronze, iron, steel, ceramic, and titanium. Most modern knives have either fixed or folding blades; blade patterns and styles vary by maker and country of origin.
In woodworking and carpentry, hand saws, also known as "panel saws", are used to cut pieces of wood into different shapes. This is usually done in order to join the pieces together and carve a wooden object. They usually operate by having a series of sharp points of some substance that is harder than the wood being cut. The hand saw is a bit like a tenon saw, but with one flat, sharp edge.
A blade is the sharp, cutting portion of a tool, weapon, or machine, specifically designed to puncture, chop, slice, or scrape surfaces or materials. Blades are typically made from materials that are harder than those they are intended to cut. This includes early examples made from flaked stones like flint or obsidian, evolving through the ages into metal forms like copper, bronze, and iron, and culminating in modern versions made from steel or ceramics. Serving as one of humanity's oldest tools, blades continue to have wide-ranging applications, including in combat, cooking, and various other everyday and specialized tasks.
A Japanese kitchen knife is a type of kitchen knife used for food preparation. These knives come in many different varieties and are often made using traditional Japanese blacksmithing techniques. They can be made from stainless steel, or hagane, which is the same kind of steel used to make Japanese swords. Most knives are referred to as hōchō or the variation -bōchō in compound words but can have other names including -kiri. There are four general categories used to distinguish the Japanese knife designs: handle, blade grind, steel, and construction.
Nakiri bōchō and usuba bōchō are Japanese-style vegetable knives. They differ from the deba bōchō in their shape, as they have a straight blade edge suitable for cutting all the way to the cutting board without the need for a horizontal pull or push. These knives are also much thinner. While the deba bōchō is a heavy blade for easy cutting through thin bones, the blade is not suitable for chopping vegetables, as the thicker blade can break the vegetable slice. The nakiri bōchō and the usuba bōchō have a much thinner blade. This does not help with cutting small bones in fish or meat, but is useful for cutting vegetables.
Yanagi-ba-bōchō, yanagi ba, or yanagi, is a long and thin knife used in the Japanese cuisine. It is the typical example of the sashimi bōchō used to slice fish for sashimi and nigiri sushi.
Usuba bōchō is the traditional vegetable knife for the professional Japanese chef. Like other Japanese professional knives, usuba are chisel ground, and have a bevel on the front side, and have a hollow ground urasuki on the back side. Usuba characteristically have a flat edge, with little or no curve, and are tall, to allow knuckle clearance when chopping on a cutting board. Usuba literally means "thin blade" indicating its relative thinness compared to other knives, required for cutting through firm vegetables without cracking them. Due to its height and straight edge, usuba are also used for specialized cuts such as katsuramuki, shaving a vegetable cylinder into a thin sheet.
A blade's grind is its cross-sectional shape in a plane normal to the edge. Grind differs from blade profile, which is the blade's cross-sectional shape in the plane containing the blade's edge and the centre contour of the blade's back. The grind of a blade should not be confused with the bevel forming the sharpened edge; it more usually describes the overall cross-section of the blade, not inclusive of the beveled cutting edge which is typically of a different, less acute angle as the bevel ground onto the blade to give it a cross-sectional shape. For example, the famous Buck 110 hunting knife has a "hollow ground" blade, with concave blade faces, but the cutting edge itself is a simple, flat-ground bevel of lesser angle. It would be difficult, if not impossible, to put a "hollow grind" onto the actual cutting edge of the blade itself, which is a very narrow and small bevel.
A sickle, bagging hook, reaping-hook or grasshook is a single-handed agricultural tool designed with variously curved blades and typically used for harvesting or reaping grain crops, or cutting succulent forage chiefly for feeding livestock. Falx was a synonym but was later used to mean any of a number of tools that had a curved blade that was sharp on the inside edge such as a scythe.
A bandsaw is a power saw with a long, sharp blade consisting of a continuous band of toothed metal stretched between two or more wheels to cut material. They are used principally in woodworking, metalworking, and lumbering, but may cut a variety of materials. Advantages include uniform cutting action as a result of an evenly distributed tooth load, and the ability to cut irregular or curved shapes like a jigsaw. The minimum radius of a curve is determined by the width of the band and its kerf. Most bandsaws have two wheels rotating in the same plane, one of which is powered, although some may have three or four to distribute the load. The blade itself can come in a variety of sizes and tooth pitches, which enables the machine to be highly versatile and able to cut a wide variety of materials including wood, metal and plastic. Band saw is recommended for use in cutting metal as it produces much less toxic fumes and particulates when compared with angle grinder and reciprocating saw.
Bread knives are used for cutting bread and are one of many kitchen knives used by cooks. The serrated blades of bread knives are able to cut soft bread without crushing it.
Serration is a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied pressure at each point of contact is greater, and the points of contact are at a sharper angle to the material being cut. This causes a cutting action that involves many small splits in the surface of the material being cut, which cumulatively serve to cut the material along the line of the blade.
A kitchen knife is any knife that is intended to be used in food preparation. While much of this work can be accomplished with a few general-purpose knives – notably a large chef's knife, a tough cleaver, a small paring knife and some sort of serrated blade – there are also many specialized knives that are designed for specific tasks. Kitchen knives can be made from several different materials.
In cooking, a chef's knife, also known as a cook's knife, is a cutting tool used in food preparation. The chef's knife was originally designed primarily to slice and disjoint large cuts of beef. Today it is the primary general utility knife for most Western cooks.
The santoku bōchō or bunka bōchō is a general-purpose kitchen knife originating in Japan. Its blade is typically between 13 and 20 cm long, and has a flat edge and a sheepsfoot blade that curves down an angle approaching 60 degrees at the point. The term santoku may refer to the wide variety of ingredients that the knife can handle: fish, meat, and vegetables, or to the tasks it can perform: chopping, dicing, and slicing. Either interpretation indicating a multi-use, general-purpose kitchen knife. The blade and handle of the santoku are designed to work in harmony by matching the blade's width and weight to the weight of the tang and the handle.
Sharpening stones, or whetstones, are used to sharpen the edges of steel tools such as knives through grinding and honing.
Sharpening is the process of creating or refining the edge joining two non-coplanar faces into a converging apex, thereby creating an edge of appropriate shape on a tool or implement designed for cutting. Sharpening is done by removing material on an implement with an abrasive substance harder than the material of the implement, followed sometimes by processes to polish/hone the sharp surface to increase smoothness.
Knife sharpening is the process of making a knife or similar tool sharp by grinding against a hard, rough surface, typically a stone, or a flexible surface with hard particles, such as sandpaper. Additionally, a leather razor strop, or strop, is often used to straighten and polish an edge.
A tomato knife is a small serrated kitchen knife designed to slice through tomatoes. The serrated edge allows the knife to penetrate the tomatoes’ skin quickly and with a minimum of pressure without crushing the flesh. Many tomato knives have forked tips that allow the user to lift and move the tomato slices after they have been cut.
A steak knife is a sharp table knife designed to efficiently and effectively cut steak. This type of knife comes in a variety of styles and sizes; however, the design often used in a steakhouse typically features a partially serrated blade and wood handle.
