From Wikipedia, the free encyclopedia
This article is about the gambling game. For other uses, see
Black
Jack (disambiguation).
Blackjack (also known as Twenty-one, Vingt-et-un
(French for Twenty-one), or Pontoon) is one of the most
popular casino
card games in
the world. Much of blackjack's popularity is due to the mix of
chance with elements of skill, and the publicity that surrounds card
counting (keeping track of which cards have been played since
the last shuffle). Not to get confused with the non casino version
of blackjack
[edit]
History of blackjack
Blackjack's precursor was vingt-et-un ("twenty-one"),
which originated in French casinos around 1700, and did not offer
the 3:2 bonus for a two-card 21.
When 21 was first introduced in the United States it was not very
popular, so gambling
houses tried offering various bonus payouts to get the players to
the tables. One such bonus was a 10-to-1 payout if the player's hand
consisted of the ace of spades and a black Jack (either the Jack of
clubs or the Jack of spades). This hand was called a "blackjack"
and the name stuck to the game even though the bonus payout was soon
abolished. As the game is currently played, a "blackjack"
may not necessarily contain a jack or any black cards at all.
[edit]
How to play blackjack
The hand with the highest total wins as long as it doesn't exceed
21; a hand with a higher total than 21 is said to bust or
have too many. Cards 2 through 10 are worth their face value,
and face cards (jack, queen, king) are also worth 10. An ace's value
is 11 unless this would cause the player to bust, in which case it
is worth 1. A hand in which an ace's value is counted as 11 is
called a soft hand, because it cannot be busted if the player
draws another card.
Each player's goal is to beat the dealer by having the higher,
unbusted hand. Note that if the player busts he loses, even if the
dealer also busts. If both the player and the dealer have the same
point value, it is called a "push", and neither player nor
dealer wins the hand. Each player has an independent game with the
dealer, so it is possible for the dealer to lose to some players but
still beat the other players in the same round.
Example of a Blackjack game. The top half of the picture shows
the beginning of the round, with bets placed and an initial two
cards for each player. The bottom half shows the end of the round,
with the associated losses or payoffs.
The minimum bet is printed on a sign on the table and varies from
casino to casino and table to table. After initial bets
are placed, the dealer deals the cards, either from one or two
hand-held decks
of cards, known as a "pitch" game, or more commonly
from a shoe
containing four or more decks. The dealer gives two cards to each
player including himself. One of the dealer's two cards is face-up
so all the players can see it, and the other is face down. (The
face-down card is known as the "hole card". In European
blackjack, the hole card is not actually dealt until the players all
play their hands.) The cards are dealt face up from a shoe, or face
down if it is a pitch game.
In American blackjack, if the dealer's face-up card is an ace or
a ten-value, the dealer checks his hole card to see if he has
blackjack. This check occurs before any of the players play, but
after they have been offered insurance (if the face-up card is an
ace). If the dealer has blackjack, all players lose their initial
bets, except players who also have blackjack, who push. (In some
American casinos, the dealer does not actually check the hole card
until after the players have all played. At that time, if the dealer
turns out to have blackjack, all players who did not have blackjack
lose their bets, and players who increased their bets by doubling or
splitting lose only the original bet, and have the additional bets
returned to them; thus, the end result is precisely as if the dealer
had checked the hole card before playing.)
A two-card hand of 21 (an ace plus a ten-value card) is called a
"blackjack" or a "natural", and is an automatic
winner (unless the dealer has blackjack as well, in which case the
hand is a push). A player with a natural is usually paid 3:2 on his
bet. Some casinos pay only 6:5 on blackjacks; although this reduced
payout has generally been restricted to single-deck games (Current
Blackjack News, Pi Yee Press).[citation
needed] This reduced payout for a natural increases the
house advantage over a player by as much as 1000 percent. The move
was decried by longtime blackjack players[1].
[edit]
Player decisions
The player's options for playing his or her hand are:
Hit: Take another card.
Stand: Take no more cards.
Double down: Double the
wager, take exactly one more card, and then stand.
Split: Double the wager
and have each card be the first card in a new hand. This option is
available only when both cards have the same value.
Surrender: Forfeit half the bet and give up the hand.
Surrender was common during the early- and mid-20th century, but is
no longer offered at most casinos.
The player's turn is over after deciding to stand, doubling down
to take a single card, or busting. If the player busts, he or she
loses the bet even if the dealer goes on to bust.
After all the players have finished making their decisions, the
dealer then reveals his or her hidden hole card and plays the hand.
House rules say that the dealer must hit until he or she has at
least 17, regardless of what the players have. In some casinos a
dealer must also hit a soft 17 (a combination of cards adding up to
either 7 or 17, such as an ace and a 6).
If the dealer busts then all remaining players win. Bets are
normally paid out at the odds of 1:1. Players who push (tie) with
the dealer receive their original bet back.
[edit]
Rules variations
Some common rules variations include:
Only one card for split Aces:
a single new card is added to each Ace and the turn ends. They are
thus regarded as 11-point cards. No other denomination is subject
to this process.
Multiple splits: If a
player splits 2 cards and receives a third card of identical value,
the hand can be split again, resulting in 3 hands. However, some
casinos only allow a single split of the first 2 cards.
Early surrender: Player
has the option to surrender before dealer checks for Blackjack.
Late surrender: Player has
the option to surrender after dealer checks for Blackjack.
Double-down restrictions:
Double-down may only be allowed on certain combinations of cards
(usually totaling 9, 10 or 11).
Double-down after split:
Double-down may not be allowed after splitting cards. The split
hands are played normally otherwise.
Split any tens: Players
may split any 2 cards which are both worth 10 points, such as a
Jack and Queen. This rule is rarely used, since 20 is a very strong
hand which is unlikely to be split.
European No-Hole-Card Rule: the dealer
receives only one card, dealt face-up, and does not receive a
second card (and thus does not check for blackjack) until players
have acted. This means players lose not only their original bet,
but also any additional money invested from splitting and doubling
down. A game that has no-hole-card doesn't necessarily mean the
player will lose additional bets as well as original bets. In some
Australian casinos for example, a player beaten by a dealer
blackjack may keep all split and double bets and lose only the
original bet, thus the game plays the same as it would if there
were a hole card.
Each blackjack variation has its own set of rules, strategies and
odds. It is advised to take a look at the rules of the specific
variation before playing. Many countries have legal acts and laws,
which determine how a casino game of Blackjack must be played. Over
100 variations exist.[2]
[edit]
Insurance
If the dealer's upcard is an Ace, the player is offered the
option of taking Insurance before the dealer checks his 'hole
card'.
The player who wishes to take Insurance can bet an amount up to
half his original bet. The Insurance bet is placed separately on a
special portion of the table, which usually carries the words
"Insurance Pays 2:1". The player who is taking Insurance
is betting that the dealer was dealt a natural, i.e. a
two-card 21 (a blackjack), and this bet by the player pays off 2:1
if it wins. It is called insurance since if the dealer has a
blackjack, the bet wins the same amount of the player's Blackjack
wager, such that if insurance is taken and the player doesn't have
blackjack but dealer does, no money is lost. Of course the dealer
can end up not having blackjack and the player can still win or lose
the blackjack bet.
Insurance is a bad bet for the non-counting player who has no
knowledge of the hole card because it has a house edge of 2 to 15%,
depending on number of decks used and visible 10-cards [3].
Essentially, taking insurance amounts to betting that the dealer's
hole card is a ten or face card. Since in an infinite deck, 4/13 of
the cards are tens or face cards, an unbiased insurance wager would
actually pay 9:4, or 2.25:1; since the bet only pays 2:1, the house
has a strong advantage. However, if the player has been counting
cards, he may know that more than a third of the deck is ten-value
cards, in which case insurance becomes a good bet.
If a player has a natural (an ace and a ten or face-card) and the
dealer is showing an ace, the dealer usually asks the player "Even
money?" instead of offering insurance. If the player accepts
the offer, he is immediately paid 1:1 for his natural, regardless of
whether the dealer has blackjack. Thus, accepting "even money"
has exactly the same payout as buying insurance: if the dealer does
not have blackjack, the player would forfeit the insurance bet and
win 3:2 on the natural, thus receiving a net payout equal to the
original bet; if the dealer does have blackjack, the player would
push on the natural and win 2:1 on the insurance wager, again
receiving a net payout equal to the original bet. Since taking "even
money" is equivalent to buying insurance, it is likewise a bad
choice for the player, unless he has been counting cards and knows
the deck has an unusually high proportion of ten-value cards.
In casinos where a hole card is dealt, a dealer who is showing a
card with a value of Ace or 10 may slide the corner of his or
her facedown card over a small mirror or electronic sensor on the
tabletop in order to check whether he has a natural. This practice
minimizes the risk of inadvertently revealing the hole card, which
would give the sharp-eyed player a considerable advantage.
[edit]
Blackjack strategy
[edit]
Basic strategy
Because blackjack has an element of player choice, players can
reduce casino advantage to less than 1% by playing optimally. The
complete set of optimal plays is known as basic strategy.
There are slight variations depending on the house rules and number
of decks.
The above is a basic strategy table for 3 or more decks, dealer
stands on soft 17, double on any 2 cards, double after split
allowed, dealer peeks for blackjack, and blackjack pays 3:2. Key:
- S = Stand
H = Hit
Dh = Double (if not
allowed then hit)
Ds = Double (if not
allowed then stand)
SP = Split
SU = Surrender (if
not allowed, then hit)
Most Las Vegas strip casinos hit on soft 17. This rule change
requires a slightly modified basic strategy table -- double on 11 vs
A, double on A/7 vs 2, and double on A/8 vs 6. Most casinos outside
of Vegas still stand on soft 17.
[edit]
Card counting
- Main article: Card
counting
Basic strategy provides the player with the optimal play for any
blackjack situation based on millions of hands played in the long
run. However in the short run, as the cards are dealt from the deck,
the remaining deck is no longer complete. By keeping track of the
cards that have already been played, it is possible to know when the
cards remaining in the deck are advantageous for the player.
Card counting creates two opportunities:
The player can make larger bets
when he or she has the advantage. For example, the player can
increase the starting bet if there are many aces and tens left in
the deck, in the hope of hitting a blackjack.
The player can use information about the remaining cards to
improve upon the basic strategy rules for specific hands played.
For example, with many tens left in the deck, the player may double
down in more situations since there is a better chance of making a
strong hand.
Virtually all card counting systems do not require the player to
remember which cards have been played. Rather, a point system is
established for the cards, and the player keeps track of a simple
point count as the cards are played out from the dealer.
Depending on the particular blackjack rules in a given casino,
basic strategy reduces the house advantage to near 0 with some
single-deck games, and less than one percent in a multi-deck
game.[4]
Card counting, if done correctly, can give the player an advantage
in the other direction, typically ranging from 0 to 2% over the
house.[5]
To counter card counting, many casinos switched from a single deck
to multiple decks, with the cards dealt out of a container known as
a "shoe".
In most US jurisdictions, card counting is legal and is not
considered cheating.[6]
However, most casinos have the right to ban players, with or without
cause, and card counting is frequently used as a justification to
ban a player. Usually, the casino host will simply inform the player
that he is no longer welcome to play at that casino. Players must be
careful not to signal the fact that they are counting. The use of
electronic or other counting devices is usually illegal.
- See also: Martingale
(betting system)
[edit]
Composition-dependent strategy
Basic strategy is based on a player's point total and the
dealer's visible card. A player's ideal decision may depend on the
composition of his hand, not just the information considered in the
basic strategy. For example, a player should ordinarily stand when
holding 12 against a dealer 4. However, in a single deck game, the
player should hit if his 12 consists of a 10 and a 2; this is
because the player wants to receive any card other than a 10 if
hitting, and the 10 in the player's hand is one less card available
to cause a bust for the player or the dealer.[7]
However, in situations where basic and composition-dependent
strategy lead to different actions, the difference in expected value
between the two decisions will be small. Additionally, as the number
of decks used in a blackjack game rises, both the number of
situations where composition determines the correct strategy and the
house edge improvement from using a composition-dependent strategy
will fall. Using a composition-dependent strategy only reduces house
edge by 0.0031% in a six-deck game, less than one tenth the
improvement in a single-deck game (0.0387%).[8]
[edit]
Shuffle tracking
Techniques other than card counting can swing the advantage of
casino blackjack towards the player. All such techniques are based
on the value of the cards to the player and the casino, as
originally conceived by Edward
O. Thorp.[citation
needed] One technique, mainly applicable in multi-deck
games, involves tracking groups of cards (aka slugs, clumps, packs)
during the play of the shoe, following them through the shuffle and
then playing and betting accordingly when those cards come into play
from the new shoe. This technique, which is admittedly much more
difficult than straight card counting and requires excellent
eyesight and powers of visual estimation, has the additional benefit
of fooling the casino people who are monitoring the player's actions
and the count, since the shuffle tracker could be, at times, betting
and/or playing opposite to how a straightforward card counter
would.[citation
needed]
Arnold Snyder's articles in Blackjack
Forum magazine brought shuffle tracking to the general
public. His book, The Shuffle Tracker's Cookbook,
mathematically analyzed the player edge available from shuffle
tracking based on the actual size of the tracked slug. Jerry
L. Patterson also developed and published a shuffle-tracking
method for tracking favorable clumps of cards and cutting them into
play and tracking unfavorable clumps of cards and cutting them out
of play. [9]
[10]
[11]
Other legal methods of gaining a player advantage at blackjack
include a wide variety of techniques for gaining information about
the dealer hole-card or the next card to be dealt.
[edit]
Variants
Pontoon is an English variation of blackjack with significant
rule and strategy differences. However, in Australia and Malaysia,
Pontoon
is an unlicensed version of the American game Spanish
21 played without a hole card; despite the name, it bears no
relation to English Pontoon.
Spanish 21
provides players with many liberal blackjack rules, such as doubling
down any number of cards (with the option to 'rescue', or surrender
only one wager to the house), payout bonuses for five or more card
21's, 6-7-8 21's, 7-7-7 21's, late surrender, and player blackjacks
always winning and player 21's always winning, at the cost of having
no 10 cards in the deck (though there are jacks, queens, and kings).
21st
Century Blackjack (also known as "Vegas Style"
Blackjack) is commonly found in many California card rooms. In this
form of the game, a player bust does not always result in an
automatic loss; there are a handful of situations where the player
can still push if the dealer busts as well, provided that the dealer
busts with a higher total.
Certain rules changes are employed to create new variant games.
These changes, while attracting the novice player, actually increase
the house edge in these games. Double
Exposure Blackjack is a variant in which the dealer's cards are
both face-up. This game increases house edge by paying even
money on blackjacks and players losing ties. Double
Attack Blackjack has very liberal blackjack rules and the option
of increasing one's wager after seeing the dealer's up card. This
game is dealt from a Spanish shoe, and blackjacks only pay even
money.
The French and German variant "Vingt-et-un"
(Twenty-one) and "Siebzehn und Vier" (Seventeen and Four)
don't include splitting. An ace can only count as eleven, but two
aces count as a Blackjack. This variant is seldom found in casinos,
but is more common in private circles and barracks.
Chinese
Blackjack is played by many in Asia, having no splitting of
cards, but with other card combination regulations.
Another variant is Blackjack
Switch, a version of blackjack in which a player is dealt two
hands and is allowed to switch cards. For example, if the player is
dealt 10-6 and 10-5, then the player can switch two cards to make
hands of 10-10 and 6-5. Natural blackjacks are paid 1:1 instead of
the standard 3:2, and a dealer 22 is a push.
Recently, thanks to the popularity of poker, Elimination
Blackjack has begun to gain a following. Elimination Blackjack
is a tournament format of blackjack.
Many casinos offer optional side bets at standard blackjack
tables. For example, one common side-bet is "Royal Match",
in which the player is paid if his first two cards are in the same
suit, and receives a higher payout if they are a suited queen and
king (and a jackpot payout if both the player and the dealer have a
suited queen-king hand). Another increasingly common variant is
"21+3," in which the player's two cards and the dealer's
up card form a three-card poker hand; players are paid 9 to 1 on a
straight, flush or three of a kind. These side bets invariably offer
worse odds than well-played blackjack.
[edit]
Blackjack Hall of Fame
- Main article: Blackjack
Hall of Fame
In 2002, professional gamblers around the world were invited to
nominate great blackjack players for admission into the Blackjack
Hall of Fame. Seven members were inducted in 2002, with new
inductees every year afterwards. The physical hall of fame is
located at the Barona
Casino in San
Diego, California. Members include Edward
O. Thorp, author of the 1960s book Beat the Dealer which
proved that the game could be beaten with a combination of basic
strategy and card
counting; Ken
Uston, who popularized the concept of team play; Arnold
Snyder, author and editor of the Blackjack
Forum trade journal; Stanford
Wong, author and popularizer of the "Wonging"
technique of only playing at a positive count, and several others.
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