Though the main purpose of dog collars has been to hold the dogs license and attach a chain or leash, modern dog collars have many functions. Some dog collars are used in dog training while others have safety features to give the dog owner peace of mind that the dog is safe.

Several dog collars are used for holding the dogs license, attaching the leash, and creative expression. Collars are available in many colors and some are rhinestone, jeweled, or have charms attached.

Anti-bark collars are designed to stop excessive barking. The dog owner pushes a button that administers a shock or sprays the dog with citronella as a deterrent to barking. Though some dog owners may have found these collars helpful, these are not recommended methods of training.

For dogs that wander away from home, there are dog collars that are used to teach the dog to stay close to home. These dog collars emit an aversive noise when the dog leaves the perimeter of the property.

Dog fences are widely used systems for keeping dogs within the boundaries of the property. The dog fence system uses a special collar that delivers warning noises and electric shocks to teach the dog to stay within the boundary of the dog fence.

If a dog tends to run away, the dog owner has the option of using a new type of collar that uses a GPS system. The GPS system allows the dog owner to find a lost dog using the Internet or a cell phone to pinpoint the dogs location.

Some dog collars are used for training a dog to walk properly with the owner. Choker chains are sometimes used, but some newer models of training collars are less likely to be abused. Some dog owners find dog harnesses useful for dogs that tend to pull on leashes.

Pinch collars are sometimes called pronged collars because they have metal prongs that apply pressure to the dogs neck. Novice dog owners should not use pinch collars. The purpose of dog collars that are designed to put pressure on the dogs neck is to train aggressive dogs or dogs that have not responded to positive training methods.