Mammals are warm-blooded animals that give birth to live young rather than laying eggs, and they can be found living in many habitats around the world including on land, in the sea, in the air and underground. They communicate in various ways including making noises and touching noses in a friendly greeting, and they live together in social groups such as packs, herds and bachelor groups. There are many different types of mammals including armadillos, bats, carnivores, hoofed animals, marine animals, primates, rabbits, rodents and moles.