Standard 52-card deck jokers, often distinguishable with one being more colorful than the other, are added to commercial decks, as some card games require these extra cards. Modern playing cards carry index labels on opposite corners or in all four corners to facilitate identifying the cards when they overlap and so that they appear identical for players on opposite sides. The most popular standard pattern of the French deck is sometimes referred to as "English" or "Anglo-American" pattern. It has been shown that because of the large number of possibilities from shuffling a 52-card deck, it is probable that no two fair card
Joker (playing card) cards provide symbols for three jokers: red, black, and white. Many decks do not provide the Joker with a corner index symbol, of those that do, the most common is a solid five-pointed star or a star within a circle. It is also very common for decks to simply use a stylized "J" or the word "JOKER" in the corner. Like sports trading cards, jokers are often prized by collectors. Many unusual jokers are available for purchase online while other collectible jokers are catalogued online for viewing. Some European games have as many as six jokers per pack. Zwicker uses