Sleep is a natural-occurring state in which the consciousness and the muscular activity are suspended. For millennia, sleep has been one of the major subjects of enquiry. The ancient Egyptians and the Chinese were greatly involved in understanding the mechanism of sleep. The mechanism of sleep remained mysterious for a long period of time until the advances of the mid-20th century.
The very old Egyptians derived the remedy for sleep by combining poppy and wine whereas the Chinese of the same period contradicted the remedy for sleep to be the time of the day and duration spent staying awake.