It seems as if there are as many different kinds of collars as there are different kinds of dogs - and choosing the right collar can be intimidating! Here is a brief explanation of the different types of collars and their uses.
Boxers require 'obedience' training and to be taught good manners - so if you have not got the time for this a Boxer may not suit you. Boxers are very intelligent dogs and require firm, fair, fun training. If you want a dog who only wants to do what you say when you say, do not get a Boxer. Boxers are a very independent breed, very willing to work with you, but unwilling to be ordered around. Trained properly, a Boxer is the most delightful companion you could wish for.
These are pretty much just what they sound like, collars that are fastened with a buckle. They are typically made of nylon, cotton, or leather, and are either flat or rolled. Buckle collars are adjustable, but do not tighten on the dog's neck once fastened. Rolled leather collars avoid the chafing or hair breakage that flat collars sometimes cause.
These are basically flat nylon buckle collars, with a plastic closure that makes getting the collar on and off a little quicker (similar to some luggage strap fasteners). These collars are also adjustable, and also do not tighten once fastened.
A special quick-release collar that will unfasten if a strong pull is placed on the collar. This collar was designed after the inventor's dog choked to death because its collar got caught on something. The collar will not unfasten when attached to a leash.
Nylon Slip (Show) Collar
Slip Collars: There are several kinds of slip collars - also referred to as chokers or choke chains. Slip collars are made of braided nylon, cotton, or leather, with "O" rings at either end. The collar loops through one of the rings, making a "P" shape. The lead is usually attached to the ring at the bottom of the "P," which allows the collar to tighten and loosen with pressure from the lead. The floating ring is called the dead ring - if a lead is attached to the dead ring, the collar will not tighten.
Metal Show Collar
Thin slip collars are frequently used in all but toy dogs in the conformation show ring. Show collars are usually made of braided nylon, cotton, or leather, or hex or serpentine metal chain. The metal show collars are not the same as training choke chains.
Limited Slip Collars
These collars are a combination of slip collars and quick-release collars. They are adjustable collars designed to tighten around a dog's neck, but to stop tightening before they actually constrict around the neck. They are good for dogs who tend to "slip" their collars, and some varieties are often called "Greyhound collars."
"Greyhound" Limited Slip Collar
These are similar to limited slip collars, except they don't have a buckle. They slid over the dog's head, and then a piece of plastic tubing (typically) is slid down to the desired tightness. Martingales are frequently used to show Toy dogs in conformation.
This is the common name of the metal training slip collar. Choke chains are still used as the primary training tool in many "traditional (jerk & praise)" training methods - when the dog is given a yank if it does not obey a command. A study done in Germany showed that choke chains cause a great deal of neck, back, and tracheal injuries to dogs. While this is not a training method discussion, it is prudent to note that any training tool used improperly can cause trauma to the dog. If you choose to use a special training tool or collar, be sure that you are shown the proper way to use it by a qualified, experienced instructor.
There are different types of chokes, primarily based on the width and weight of the links. The heavier the chain, the less smooth the sliding is (in the jerk & praise method, the collar slides to tighten on the dog's neck when a "correction" is given). Chokers should be used as training collars *only,* and should never be used on puppies. Tags should not be attached to chokers, as they will interfere with the sliding action. There are wide-link chokers for long-haired dogs, as often the chain will pull out the hair around a long-haired dog's neck.
Prong or Pinch Collars
These are used for the same purposes as the choke collar, to "correct" the dog by yanking on its neck if it does not comply. The prong collar is actually far safer than the choker - the study in Germany mentioned above also evaluated prong collars, and found no neck/back/trachea injuries as a result of correct use of this collar. Prong collars are commonly used with dogs who pull while on lead - it is worth noting that the individual prongs do wear and stretch, and it is not uncommon for the collar to spring open while on the dog. For this reason, a back-up collar should also be worn and hooked to the leash (or a second leash). Like a choker, this collar is a training tool and should be used with proper instruction - and again should never be used on puppies.
Head halters (Gentle Leaders, Halti, Promise) are also commonly used for dogs that pull. They are supposed to mimic a halter used on horses. However, unlike a horse halter, which sits down on the bridge of the nose, dog head halters sit right below the eyes, and thus many dogs are uncomfortable with them. Head halters are not muzzles - the dog can still drink, eat, bark, and bite with one one. There has been some concern expressed that the dog could hit the end of the lead and snap its head around, causing injury to the neck. While this might happen, it illustrates the dangers of misusing a training tool. The head halter is intended for use when the dog is walking at your side, not when it is running away from you (for example, on a Flexi-lead).
More about the head alters at http://www.boxerworld.com/forums/view_boxers-and-head-halters.htm.
Some people use harnesses in an attempt to stop their dogs from pulling when on lead. This is a very contradictory use of the device - sled and carting dogs, who are *supposed* to pull, wear harnesses as a matter of course, as they offer the most effective means of weight distribution to enable the dog to pull many times its own body weight.
Often called "remote" collars by advocates and "shock" collars by detractors, these devices deliver an electrical stimulus to the dog as a "correction." A low-level stimulus is given at first, and then if the dog continues to disobey the intensity is increased, although many feel that this serves the purpose of desensitizing the dog to the stimulus. Electronic collars are strictly for training and should never be used without a professional's guidance. Improperly used, these collars can destroy a dog's self confidence, desire to work and general good will.
With all collars, proper fit is of vital importance. Non-slip collars should be loose enough to allow you to fit two fingers between the collar and the neck of the dog (without choking the dog). Slip/choke collars, prong collars, head halters and harnesses should be fitted with the help of a professional (*not* the stockperson at the pet store) who is experienced in their use, since improperly fitted collars will result in incorrect usage.
Many trainers feel that the best training collar is no collar at all. If you start out training on a collar, the dog may learn that it has to obey *only* when the collar is on. Collars are, at best, training tools - and at worst, crutches. Anything other than a flat buckle or quick-release collar should be used *only* during training sessions, and the goal should always be to move away from needing the training collar. A "trained" dog that will only obey commands when wearing a collar is not trained at all.