Condition of sleeping is called a rest and relaxation of the body muscles. The awakening state of consciousness is more or less totally not in the muscles. The muscles, tissues and other sensuory feelings being totally under the unconscious state, gives sleep to the human being. All the time the consciousness and the brain (the organ), is fully alert till our last breath, explaining the fact the brain is not sleeping at all. The condition of our tiresome feelling in our total body system takes the relaxation action by the muscles alone. Sleeping is a condition of the brain. This condition varies from person to person because of the muscles relaxation.