The brain is one of the organs (major parts) of the body. Most animals have brains, always in the head, and usually close to the parts of the body that sense the surroundings, such as eyes, nose, ears and mouth.

A human brain is made with 33 billion nerve cells (neurons).

The purpose of the brain is to control all other parts of the body. It does this through the nerves (the nervous system), causing, for example, muscles to contract or relax.

Although it is clear what the brain does, we still do not know exactly how it does what it does, especially in the area of thinking. That remains for future scientists to work out.