Dog varieties, also known as dog breeds, refer to the different types of dogs that have been developed through selective breeding. Each breed has unique characteristics, such as size, coat type, and temperament. For example, Labrador Retrievers are known for their friendly nature, while Chihuahuas are much smaller and often more energetic. There are hundreds of dog breeds worldwide, categorized into groups like working, herding, and toy breeds. Each group serves specific purposes, such as German Shepherds being used for police work and Poodles excelling in dog shows. Understanding these varieties helps potential dog owners choose the right breed for their lifestyle.