A small dog is typically defined as a canine that weighs less than 20 pounds and stands under 16 inches tall at the shoulder. Breeds such as Chihuahua, Pomeranian, and Yorkshire Terrier are common examples of small dogs. They are often known for their playful and affectionate nature, making them popular companions for families and individuals alike. Small dogs usually require less space than larger breeds, making them suitable for apartment living. Despite their size, they often have high energy levels and need regular exercise. Proper training and socialization are essential to ensure they develop good behavior and interact well with other pets and people.