Russell Foster : Why do we sleep?

Russell Foster at TEDGlobal 2013  (transcript)
Why do we sleep?
Summary
It'll be easy to understand thinking at first why the question of why we sleep appears.
It's because we tend to think that we don't do anything while we are asleep. We want to play games, to watch TV and to read books and so on, though, we have to sleep. Furthermore, in the past, Thomas Edison seemed to say that sleep was a criminal waste of time.

However,  there has been the prophetic words that sleep was the gold chain that ties health and our bodies together so sleep is an incredibly important part of our biology in fact.

Sleep is thought as a source of restoration 1) and energy conservation 2).  it's intuitive. It's thought that brain processing and memory consolidation. 3) It means when we are tired and we lack sleep, we have poor memory, poor creativity, and poor judgment. Being tired leads you to sickness and having stresses. Sustaining stress associates with sleep loss but it leads to suppressing immunity and weight gain.

It can be said that for making our lovely day, sleep is important.

Words in this story
slumber /noun/ a sleep.
consolidation /noun/ merger, combination, union,
prophetic /adj/ accurately describing or predicting what will happen in the future.
restoration /noun/ recovery
conservation /noun/ preservation