There are several types of dog training collar available on the market from the electronic dog training collar, to the choke collar. Electronic dog training collars are sometimes called 'electric'. They are effectively the same thing. One of the more popular makes is the Innotek collar'.
If you have a small dog, it is worth remebering that you can buy specialized training collars just for small dogs.
Electronic Dog Training Collar
The electronic dog training collar is used by some, to train the dog out of unwanted behavior patterns such as barking and digging etc. The electronic dog training collar consists of a remote control, and a collar that will stimulate the dogs' neck with a mild electric shock when the remote control is pressed. This, over time will discourage the dog from behaving in an unwanted manner.
Electronic dog training collars are viewed as a controversial way to train a dog by some groups as it is punishing the dog. A lot of dog trainers prefer positive reinforcment over punishment.
There are alternative types of dog training collar available such as the 'choke collar'.
Choke Collar
For obedience training, a choke collar or 'choke chain' would be best suited. These collars comprise of a slip loop that tightens around the dogs neck if it pulls on a leash too much. When the dog stops pulling, the chain loosens off. Many people consider the use of a choke collar as unnecessary but used in the right circumstances, this type of collar can be an effective training aid.
It is extremely important to only use a choke collar when training and when the dog is supervised. You must NEVER let your dog out alone with a choke collar on. If the dog becomes caught on something they may easily choke themselves.