A one-way deck is a deck of
playing cards
A playing card is a piece of specially prepared card stock, heavy paper, thin cardboard, plastic-coated paper, cotton-paper blend, or thin plastic that is marked with distinguishing motifs. Often the front (face) and back of each card has a Pap ...
where the back of the cards has a pattern that can be oriented to have a "top" and "bottom".
Magicians and
card sharp
A card sharp (also card shark, sometimes hyphenated or spelled as a single word) is a person who uses skill or deception to win at card games (such as poker). "Sharp" and "shark" spellings have varied over time and by region.
The label is not a ...
s can use the orientations of cards in one-way decks to encode information that allows them to perform
card trick
Card manipulation, commonly known as card magic, is the branch of Magic (illusion), magic that deals with creating effects using sleight of hand techniques involving playing cards. Card manipulation is often used in magical performances, especia ...
s.
A certain number of the faces of playing cards are not symmetrical, and therefore can also be used as "pointer cards" (the seven of any suit, for instance, whose odd
pip is off-center on most modern decks). When all aligned, these cards allow an otherwise ordinary deck (where the backs are all identical and symmetrical) to be used as a partial one-way deck.
See also
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Trick deck
A trick deck is a deck of playing cards that has been altered in some way to allow magicians to perform certain card tricks where sleight of hand would be too difficult or impractical.
Trick decks Brainwave deck
The Brainwave deck is a lesser-k ...
*
Edge sorting
Edge sorting is a technique used in advantage gambling where a player determines whether a face-down playing card is likely to be low or high at casino table games by observing, learning, and exploiting subtle unintentional differences on the ba ...
*
Card marking
Card marking is the process of altering playing cards in a method only apparent to marker or conspirator, such as by bending or adding visible marks to a card. This allows different methods for card sharps to Cheating in poker, cheat or for magic ...
References
Playing card decks
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