A terrier breed is a type of dog that is known for its small size and feisty personality. The three most popular terrier breeds are the Yorkshire Terrier (Yorkie), the Skye Terrier, and the CAIRN Terrier. The Yorkie is a small, toy-sized breed with a long, silky coat and a lively, playful personality. The Skye Terrier is a medium-sized breed with a double coat and a loyal, independent nature. The CAIRN Terrier is a small, sturdy breed with a wiry coat and an alert, active temperament. All three breeds are intelligent, energetic, and make excellent companions.