Mating is how some animals make babies or offspring. It's kind of like when mommy and daddy made you! When animals mate, the boy animal (called a male) has something called sperm, and the girl animal (called a female) has something called eggs. The sperm from the boy and the egg from the girl come together and make a baby!
Different animals mate differently. Some animals like birds have a special dance they do to show they want to mate. Other animals like lions have big fights to see which boy will get to mate with the girl. Some animals even mate for life and only make babies with one other animal all their life!
Mating is really important for animals because it helps their species keep going. Just like how mommy and daddy made you, when animals mate and make babies, those babies grow up to be big animals who can make their own babies. And then those babies grow up to be big animals who can make their own babies. And the cycle keeps going and going!