Sleep is a gift. It relieves mental anxiety and keeps you both mentaly as well physicaly alert. If you have studied Shakespeares Play, Macbeth, you will know that the Shakespeare has emphasised on lack of sleep to Macbeth when he slained the King, while he was guest in his house.Macbeth could not sleep and even his wife Lady Macbeth also suffered from lack of sleep. This indicated that sleep is very important in one's life.