Nikola Tesla, Franz Kafka, and Winston Churchill all practiced polyphasic sleep.
According to the National Institutes of Health, we spend about 26 years of our life asleep, one-third of the total. The latest research states that between 6.4 and 7.5 hours of sleep per night is ideal for most people. But some need more and others less. A contingent out there, mostly women, do surprisingly well on just six hours.