The brain is a jelly-like substance, which in adults weighs about three pounds. It is divided into three parts: the brain stem, which is an extension of the spinal cord, the forebrain (which consists mainly of the cerebrum) and the cerebellum. 

The forebrain and cerebellum are divided into two hemispheres which are linked by a thick band of nerve fibers and these hemispheres have areas, called "lobes," which perform specific functions. The brain's surface lies in rather ugly, wrinkled folds. Traditionally referred to as one's "gray matter," it does, indeed, contain gray nerve cell bodies which surround a smaller mass of white nerve fibers. 

The brain, like the heart, is protected by a buffer zone. This, in the form of fluid, may be the source of "water on the brain," but it is very necessary to our survival. Only these pools of fluid and the skull protect the brain from the bumps and grinds of daily living which would damage this fragile organ. 

With them, we are able to think, reason, love, forgive, create and remember, as well as to survive through automatic processes such as breathing and digesting, and we have reflexes which signal in case of "fight or flight" emergencies. Just think of it!