Parts of a Knife

Even since the beginning of history, knives have been used by people. There are many types of knives that were made for many different purposes. Some were made to fight with, others to cut food or carve wood.

In prehistoric times our ancestors used flint blades and sharpened stones for cutting and skinning animals. These kinds of cool knives had one major problem; they would break easily and rust easily as well. So, over time early man learned how to make their own metal for making better weapons and tools.

Parts of a Knife

Most people are familiar with the general idea of a knife but not many people know the different parts that make up this tool. Here is a detail about the different parts and their working: (1) blade, (2) edge, (3) spine, (4) bolster and tang, and (5) handle.

  • Blade

The blade is the cutting instrument of the knife. It is the part that does the cutting and can be identified by the fact that it possesses a sharp edge when this tool is viewed from its side (top). The edge is created by a process called "grinding", which involves striking the blade with an abrasive material (usually stone) to produce a sharp edge. 

The process of grinding can also be used to sharpen dull blades, although this process typically results in the loss of one or both sides of the blade. These tools have only one sharp side, which is known as having a "single-sided edge". And with both sides sharpened are known as having a "double-sided edge".

The blade can be differentiated from the spine at the thickest part of the knife. It is called the spine because it is on this part of the knife that stress is applied when cutting. The blade is mostly made up of metal but has a softer section in its center to allow for flexing while applying stress during cutting. 

This softer section is called the "bend". The bend allows for a small amount of giving when pressure is applied; without it, blades would be more brittle and less able to withstand stresses caused by cutting through hard materials.


  • Edge

The edge is the part that comes in contact with the ground or other objects when cutting. It can be identified by the fact that it has serrations. A serrated edge, or "sawtooth" edge, is a type of edge used on many knives and allows for a better grip during cutting, especially when repeatedly sawing through various materials. 

Serrations are small teeth that can be found on either side of the blade and help reduce slipping during cutting. A knife with a pointed tip to its blade is said to have an "acute" tip in contrast to one with a blunt tip; this refers to how much of the blade's surface is flat.

  • Spine

The spine is the thickest part of the blade. The spine can be identified by the fact that it is on this part of the knife that an inscription, also known as a "branding" or "maker's mark", will be found. A knife with a spine that is particularly thick and heavy is said to have a "bolster".

  • Bolster

The bolster is a piece of metal that assists in stabilizing the knife during use. It can be identified by its rectangular shape, which matches up with the three sides of the handle (i.e., it covers the blade but not either side).


  • Tang

The tang is the protruding piece of metal that connects the blade to the handle. It can be identified by the fact that it is on this part of the knife that an inscription, also known as a "branding" or "maker's mark", will not be found. The tang can be differentiated from the bolster at its thickest point.

Since these tools are made out of metal, they cannot bend as other objects do, so they rely on a "bend" in their center to help hold their shape and keep them rigid. All of these are characterized by at least one "bend", which is the point where the blade meets the handle of a knife.

The location and shape of this "bend" differ among knives. Some knives have both a "bend" and a "tang", while some only have one or the other. Finally, some only appear to have a bend but actually possess both. The location and shape of these various components are what distinguish different types of knives from each other. 

For example, on one end, there is a variety of hunting knives with sharp points; on the other end, there are bread knives that have serrated edges rather than points toward their ends (i.e., they lack both point and tang).

Material Used in Knife Making

Knives are typically made of a combination of metallic and nonmetallic materials including:

  • Hand-Forged Knives

Tooled or hand-forged steel knives with an edge that is held by clamping the blade's tang into a form using wood, stone, or bone tools, then heating the blade red-hot in a forge to harden it, quench it in water to temper it and grind away excess stock.

  • Stainless Steel

Stainless steel is one of the most common knife materials used. It consists of iron (cobalt) processed by oxygen and nitrogen from molten pig iron at temperatures up to about 1,800 degrees Celsius (3200 degrees Fahrenheit), then hardened in a magnetized crucible under pressure to increase hardness and enhance corrosion resistance.


  • Alloys

Alloys such as D2, H1, A1, and 154CM can be used for knife blades and make very good knife blade steel choices.

  • High Carbon

High carbon steel is a low alloy steel that contains up to 0.6% Carbon. This type of metal typically has a hardness of Rockwell 61 to 63 and is inexpensive to work with in manufacturing knives, but it does have some drawbacks: it may rust easily and will not hold its edge for long periods of time without sharpening. 

  • High-Speed Steel

High-speed steel (HSS) is high-speed steel in which the carbon content is very low. HSSs are used to make extremely high-quality knife blades but are expensive to manufacture.

  • Hardened Steel

Tool steel consists of any of a large group of hardened steels used for making hand tools, or cutting tools such as knives and machine tools. The name refers to their original application (to cut or shape wood or stone), even though many tool sheets of steel are now used to make other products, such as machine parts, appliances, and surgical instruments. 

There are many types of materials used to make tactical combat knives. 

Knife Blade Types

The two main types of knives are fixed blade knives (or solid blades) and pocket knives or folding knives (or folders). Fixed-blade knives have an immovable blade that does not fold or retract into the handle, while folding knives, as the name suggests, have a hinged or pivoted blade that folds down into the handle. The "fixed-blade" category includes metal and non-metal blades.

Folding blade knives can be categorized depending on the locking system they employ. The "slip-joint" uses only the friction between a pivot and a notch to hold the knife open. The "screwless" uses a screw to hold the blade closed and the "automatic" uses a button to keep the blade closed.


Knife types generally fall into specific types, some of which may be hybridized or combined. For example, more than one type of fixed-blade knife can feature a folding tang that allows it to close into a handle, as well as some locking system characteristic of fixed-blade knives. 

They also can be chosen by their steel construction: stainless steel, carbon steel, and high-speed steel (HSS). Stainless steel is an alloy of iron that resists corrosion from many elements including rust or oxidation from water or other liquids.

Knives are the Most Versatile Tools!

Knives are versatile tools. They're perfect for food preparation, defense, and any other assortment of odd jobs. Every set of knives you purchase should include a couple of essential pieces that every home cook should have: 

serrated blades for cutting bread and slicing tomatoes; a chef's knife for chopping and dicing vegetables; honing steel to keep your knives sharpened, and perhaps even a paring knife for peeling fruit or trimming vegetables. An important factor in choosing them is whether you will use them regularly or not.

The following knives can be helpful, but maybe a bit too specialized for some uses and may not be necessary for everyone: 

a boning knife for taking the meat off of cooked bones or skinning poultry; fillet knives for cleaning and cutting fish; cleavers for cutting through bones and joint cartilage; a plastic knife that's perfect for spreading soft butter on warm toast; and a sharpening steel, which is used to hone the blade of your knife, keeping it sharp.