Not enough sleep or disruptions to the sleep-wake cycle (such as those that may occur with shift work or travelling to a different time zone) cause the physiological state known as fatigue. Staying awake for 24 hours leads to a reduced hand-to-eye coordination that is similar to having a blood alcohol content of 0.1.
There are 13 hearts in a standard 52 card deck. There are also 13 diamonds, 13 spades and 13 clubs.
Most modern decks have 52 playing cards. A full deck consists of 4 suits of cards, each with its own ace, ranks from two to ten, a jack, a queen, and a king. Although two to four jokers may be found on most decks, they are not played in card games.