Knives can be categorized based on either form or function. Below you will find a list of knives categorized by knife form and knife function.
Knife Types by Form
Knives exist in several styles:
Fixed Blade Knives
A fixed blade is a knife in which the blade does not fold and extends most of the way into the handle. This type of knife is typically stronger and larger than a folding knife. Activities that require a strong blade, such as hunting or fighting, typically rely on fixed blade knives. Some famous fixed blade designs include the Ka-bar and Bowie knives.
A folding or pocket knife is one that has a pivot between handle and blade, allowing the blade to fold into the handle. Most folding knives are small working blades, pocket knives are usually folding knives.
Some folding knives have a locking mechanism:
- The most tranditional and commonplace lock is the slip-joint. This isn't really a lock at all, and is found most commonly on traditional pocket knives. It consists of a backspring that wedges itself into a notch on the tang on the back of the blade.
- The lockback is the simplest true locking knife. It is found on most traditional locking knives. It is like a slip-joint, but the lock consists of a latch rather than a backspring. To disengage, one presses the latch on the spine of the knife down, releasing the tang.
- The linerlock is the most common today on folding knives, especially so-called "tactical" folders. Its main advantage is that it allows one to disengage the lock with one hand. It consists of a liner bent so that when the blade opens, the liner presses against the rear of the tang, preventing it from swinging back. To disengage, you press the liner to the side of the knife from where it is attached to the inside of the scales.
- The framelock is a variant of the linerlock, however, instead of using the liner, the frame functions as an actual spring. It is usually much more secure than a liner lock.
- There are many other modern locks with various degrees of effectiveness. Most of these are particular to single brands, most notably Benchmade's AXIS(tm) lock and SpyderCo's Compression(tm) lock.
Many folding knives (particularly locking models) have a small knob, or thumb-screw that allows the user to open the knife quickly with one hand.
Knife Types by Function
In general, knives are either working (everyday-use blades), or fighting knives. Some knives, such as the Scottish Dirk and Japanese Tanto function in both roles. Many knives are specific to a particular activity or occupation:
- A hunting knife is normally used to dress large game. It is often a normal, mild curve or a curved and clipped blade. Hunting knives are a staple in the extensive world of knives. The term "hunting knife" is used loosely to mean any standard straight blade sheath knife that is at least somewhat geared towards real hunting use. In reality most of these knives are never used to dress an animal or for hunting related uses. There are some types of knives that are made specifically for hunting practices. The use of a "skinning knife" is obvious. They generally have a short, tough, razor sharp blade that is designed to easily seperate hide from flesh. Skinning knives will sometime have a dull, barbed hook on the tip of the knife for eviscerating game. This is often reffered to as a "gut hook." There is no perfect "hunting knife". The 'right' knife will be determined by the specific use, kind of game, and hunters preference of materials and style. There is certainly no lack of choice for someone who is looking for a knife made for hunting purposes.
- A stockman's knife is a very versatile folding knife with three blades: a clip, a spey and a normal. It is one of the most popular folding knives ever made.
- Utility, or multi-tool knives may contain several blades, as well as other tools such as pliers. Examples include Leatherman, SOG, Gerber and Victorinox (The "Swiss Army knife") tools.
- An electrician's knife is specially insulated to decrease the chance of shock.
- A kukri is a Indian fighting and utility knife with a deep forward curve.
- A machete is a long wide blade, used to chop through brush. This tool (larger than most knives, smaller than a sword) depends more on weight than a razor edge for its cutting power.
- A survival knife is a sturdy knife, sometimes with a hollow handle filled with equipment. In the best hollow-handled knives, both blade and handle are cut from a single piece of steel. The end usually has an O-ring seal to keep water out of the handle. Often a small compass is set in the inside, protected part of the pommel/cap. The pommel may be adapted to pounding or chipping. Recommended equipment for the handle: a compass (usually in the pommel). Monofilament line (for snares, fishing), 12 feet of black nylon thread and two needles, a couple of plastic ties, two barbed and one unbarbed fishhook (unbarbed doubles as a suture needle), butterfly bandages, halizone tablets, waterproof matches.
- Special purpose blades may not be made of metal. Plastic, wood and ceramic knives exist. In most applications, these relatively fragile knives are used to avoid easy detection. Custom-made knives with diamond edges are used to make ultrathin slices of samples for use with an electron microscope.
For whittling (artistic wood carving) a blade as short as 25mm (1 inch) is common.
Serrations on a blade "saw" through the item being cut and stay sharp for a long time. The points protect the slicing areas from nicks. A good serration pattern will stay sharp several times as long as a straight edge.
The edge is sharpened at different angles for different purposes. 15 to 25 degrees is a good all-around angle. Slicing knives should have sharper angles, down to ten degrees. Chopping knives need blunter angles, out to thirty degrees.
Other Types of Knives
- Boot Knives - these knives are meant to be carried inside of a boot, usually to conceal the fact that you are carrying a knife.
- Butterfly Knives - The butterfly knife is an interesting knife that you can spin and swirl in your hand, opening and closing the blade with each revolution. It was kind of fad amongst martial artists and teenagers duing the 1980's.
- Collector Knives - these are generally purchased for display, not use, although many collector knives are fully functional.
- Dagger Knives - short, bladed weapon designed for stabbing rather than cutting.
- Diving Knives - Diving knives are practical tools used by divers to cut, measure, pry, dig or pound underwater. A dive knife is NOT a weapon. (Don't use your knife to hunt or wrestle sharks.)
- Fillet Knives - Fillet knives are from 6" to 12" and generally have narrow flexible blades designed to fillet a fish.
- Neck Knives - Neck Knives are simply knives that have a case or sheath that can be carried like a necklace. They offer a convenient alternative to traditional folding knives or pocket knives. There are several styles of and sizes neck knife from several different manufacturers but all should be lightweight.
- Tanto Knives - specialty knives which contain the unique "tanto" blade
- Thowing Knives - knives that are intended to be thown. There are a wide variety of knife-throwing techniques used by hobbiests and professionals.
Some of this information is taken from the Wikipedia.