The brain is the part of the body which lets animals make sense of things. It gets input from sense organs, and changes behavior in response to this information. In humans, the brain also controls our use of language, and is capable of abstract thought. The brain is the main control centre of the whole body. The brain is made up of special cells called nerves, which are connected with each other and with other nerves in our body. In all animals the delicate brain is protected in some way. In ourselves, and all vertebrates, it is protected by the bones of the skull.