There may be about 3 and 3 million species of animals in earth. Animals have existed for millions of years. The earliest animals were soft bodied. There are so many amazing types of animals in planet that each has their own unique and distinguished characteristics that belongs to particular each of them. They live in different parts of world and some of animals include cat, dog, elephant, sharks, dogs, horses, dolphins, giraffes, birds, fishes, wolves and many more. Animals are divided into six groups, amphibians, birds, fish, invertebrates, mammals and reptiles. Fish may evolve from a creature similar to like coral-like sea squirt. There are many types of fish and have great importance to human beings, because of their usage as a food to them. Whale, shark and jelly fish are some well known fishes. Amphibians were first to move from life in water to life on land and there are about 5000 to 6000 species of amphibians alive today. Frog, smooth newt, fire salamander are examples. Reptiles have dry skin with scales or scutes. They have backbone and are cold blooded and can harm human beings. They start evolving 330 million years ago. But today very few reptiles remain on planet that includes crocodile, snakes, lizards etc. Birds are feathered, winged, egg-laying animals. They are vertebrate. There are many types of birds. Some are very beautiful, learn from humans and can also speak like parrots. Bird’s species are about 9800 to 10,050. Humming birds is smallest bird in the world. Mammals have backbone, have hairs on body. Mammals display a remarkable array of adaptations that enable them to inhabit a wide range of habitats. Invertebrates do not have backbone include butterfly etc.