There are two kinds of animals: vertebrates which have backbones, and invertebrates, which do not.
Fish are cold-blooded, live in water and breathe using gills. Their skin is scaly and with the exception of sharks, which give birth to live young, they lay eggs. Carp, clownfish, bass, snakeheads, swordfish, tuna and eels are other examples of fish.
Amphibians are cold-blooded animals and begin life in the water, breath through gills. When they are full-grown, they breathe through their lungs and can walk on land. They lay eggs. Some examples of amphibians are frogs, toads, newts, and salamanders.
Reptiles are cold-blooded animals and have lungs. Their skin is scaly. Most reptiles lay eggs. Reptiles include lizards, turtles, snakes, alligators, and crocodiles.
Birds are warm-blooded animals and have wings and feathers. All birds lay eggs and most can fly except for ostrich and penguins cannot. Other examples of birds are eagles, ducks, parrots, seagulls, storks, and flamingoes.
Mammals are warm-blooded and, with the exception of the platypus and the echidna, give birth to live young. Mammal mothers breast feed their youngs. Most mammal have hair or fur and live on land, except for porpoises, dolphins and whales, which live in the water. Moose, bats, tigers, raccoons, bears, otters, dogs, cats, gorillas, and humans are all mammals.
Sponges live in the water and are immobile. They get their food by filtering tiny organisms that swims by.
Coelenterates use their mouths not only to eat with but also to eliminate their waste. There are stinging tentacles around their mouths. Examples of coelenterates are corals, hydras, jellyfish and sea anemones.
Echinoderms live in the sea and have exoskeletons, which means that their skeleton or supporting structure is located on the outside of their bodies. Some echinoderms are sea urchins, brittle stars, starfish, and sand dollars.
Worms live in a variety of places, including underwater, in the ground and even inside other living creatures. Examples of worms include tapeworms, flukes, pinworms, leeches, night crawlers and earthworms.
Mollusks have soft bodies. To protect themselves, some have hard shells. Examples are clams, oysters, mussels, octopuses, scallops, squids, and snails are all mollusks.
Arthropods have bodies that are divided into different parts or segments. They also have exoskeletons. Arthropods includes crustaceans, such as lobsters, crabs, shrimps and barnacles; arachnids such as spiders, scorpion and ticks; centipedes, millipedes and all insects such as butterflies, ants, bees, dragonflies and beetles.