Human Body

The brain, the heart, and the incredible machine you live inside every day.

100 billion neurons, unlimited storage capacity, and it uses more energy than any other organ.

It beats 100,000 times a day and pumps enough blood to fill a swimming pool every week.

You were born with 300 bones, but adults only have 206. Where did the others go?

Why we spend a third of our lives asleep: the stages of sleep, the science of REM dreaming, and what the brain does while the body rests.