* Humans ARE animals. We belong to the animal kingdom. All animals share certain characteristics like being multicellular, heterotrophic (meaning they get nutrients from other organisms), and capable of movement.
* Humans are specifically mammals. Within the animal kingdom, we belong to the class Mammalia. This means we share traits like having mammary glands, fur or hair, and giving birth to live young.
So, a human is both an animal and a mammal. It's like saying "My dog is a dog and also a mammal." There's no contradiction, just a way of classifying organisms at different levels.