Mammals (Mammalia) are a class of vertebrate homeothermic amniotes (of "warm blood") that possess milk-producing mammary glands with which they feed the young. Most are viviparous (with the notable exception of the monotrematas: platypus and echidnas). A clear example of a mammal is man and his best friend, the dog.
This should not be included in the notes, because it is scientifically approved that mammals have the capacity to produce milk and give this food to their young, which is vital for humans or dogs as in the example