E-collars, or electronic collars, are devices used primarily in dog training. They deliver a mild electric stimulation to the dog's neck to reinforce commands or discourage unwanted behaviors. E-collars can be adjusted for intensity and are often used in conjunction with positive reinforcement techniques. These collars are popular among trainers and pet owners for their ability to communicate with dogs over long distances. They can be particularly useful for training in open areas or for recall training. However, proper use and understanding of the device are essential to ensure the dog's well-being and effective training outcomes.