Dolphins are classified as mammals, specifically within the suborder Cetacea, which includes whales and porpoises. They belong to the family Delphinidae, which encompasses around 36 species, including the well-known bottlenose dolphin. As mammals, dolphins are warm-blooded, breathe air through lungs, and nurse their young with milk produced by mammary glands. They possess streamlined bodies adapted for aquatic life and are known for their intelligence, social behavior, and complex communication skills. Dolphins inhabit various marine environments and are often recognized for their playful nature and acrobatics in the water.