Mammals:
Are Warm-blooded (i.e. with an internal heat source and regulation),
Are Viviparous - the Duck-billed Platypus and one or two other animals are warm-blooded but lay eggs, and strictly speaking belong to their own group, the monotremes, not mammals.
Lactate - to feed their own young directly.
Have hair, to greater or lesser extent depending on species and (in our species at least) sex.
The birds are warm-blooded but are all oviparous, do not lactate and have feathers not hair - and are closer to reptiles than to mammals.
if your talking about what is the difference between mammals and non-mammals, the difference is: the non-mammals lay eggs and the mammals just have baby's out their vagina.. XD
mammals eat other species and other animals
hair
The other animals are Mammals is Dolphin,Cat,Dog,Cheetah,Lion,Tiger And Others Every Mammals is Dangerous And Some Mammals Extinc And Others Is No Longer Exist Like a Dinosaur And Dinosaur is Very Dangerous Too.
Many other animals, such as most mammals and birds.
they are living
Predators like lions, T-Rex, and other mammals
The presence of a backbone (a "vertebrae") does not DEFINE a mammal because other animals also have backbones, eg reptiles, birds and fish - these animals are also "vertebrates".Mammals are mammals because they are the only animals to have fur/hair and feed their young on milk.
Hair and mammillary glands.
Mammals can give birth,where few animals cant
Mammals are different than other animals for a few reasons, but the main one is the presence of hair or fur. Another reason is that mammals have mammary glands.
All mammals have fur, some other animals can have fur e.g the platypus which lays eggs but has fur so it has characteristics of both mammals and reptiles but all mammals have fur.