The game of Piquet or Cent , the game's English
name in period, has been played since at least the end of the 15th century.
It is mentioned in literary and scholarly works as diverse as Rabelais's
Gargantua et Pantagruel (1534) and Girolamo Cardano's Liber
de Ludo Aleae (Book on Games of Chance, 1564), a treatise on probability
theory. One of the earliest instruction manuals for a card game was Le
Royal Ieu du Piquet Plaisant et recreatif, The Royal and Delightfull
Game of Piquet.
To Play Piquet
Piquet is a game for two players, using 36 cards
(sixes through Aces). The dealer is called the younger ; the other
player is called the elder. Each hand of piquet is divided into five
parts:
 Blanks and discards,
 ruffs,
 sequences,
 sets, and
 tricks.
The parts are played in that order. Scores are
counted in each part of the hand; the first player to score 100 points is
the winner. This may take several hands. I recommend using either a score
sheet or a cribbage board to keep score.
The players cut for the deal of each hand, and the holder of the low card
is the dealer. Each player is dealt 12 cards in increments of 2 to 4 cards.
The remaining stock of 12 cards is placed between the players.
Playing the five parts of Piquet
 Blanks and discards:
 Each player may discard up to 8 cards, and
draw as many from the stock. The elder discards and draws first, followed
by the younger. Both players must discard and draw at least one card.
A hand with no face cards is called a blank.
If the elder has a blank, she may declare the blank and the number
of cards she is going to discard. After declaring, she shows her hand
to the other player. The younger discards and draws her new cards
if she does not have a blank. Then the elder discards, draws and receives
10 points. However, if the younger also has a blank, she declares
and shows it. No points are awarded, and play continues as though
neither had a blank. The younger may not declare a blank independently.
 Ruffs:
 A ruff is the total number of points in
a suit. Aces count 11 points, face cards count 10 points, and number
cards count their number. The elder declares the number of points in
her largest ruff. If the younger has an equal or higher ruff, she declares
her points, too. If the ruffs are equal, then neither player scores.
If not, the high ruff receives points for all cards in the hand. 1 point
is scored for each 10 points in the hand. 1 to 4 points are rounded
down, and 5 to 9 points are rounded up. The loser may ask to see the
winning ruff.
 Sequences:
 A sequence is a group of three or more consecutive
cards in a suit. The elder declares the number of cards in her longest
sequence. If the younger has an equal or higher sequence, she declares
it. If the sequence sizes are equal, both declare the largest card in
the sequence. If both sequences are of equal length with the same high
card, then neither player scores. Otherwise, either the longest sequence,
or the sequence containing the largest card receives points for all
sequences in the hand. Sets of three and four score 3 and 4 points,
respectively. Sets of five and up score 10 points plus the number of
cards in the sequence. The loser may ask to see the winning sequence.
 Sets:
 A set is three or more tens, Jacks, Queens, Kings
or Aces. The elder declares the number of cards in her largest set.
If the younger has an equal or higher set, she declares it. If the set
sizes are equal, the set card is declared. The largest set, or, if both
have sets of equal size, the set with the highest card receives points
for all sets in the hand. Sets of three score 13 points, and sets of
four score 14 points. The loser may ask to see the winning set.
 Tricks:
 Tricks are played like notrump tricks
in bridge. For the first trick, the elder leads a card, and the younger
tries to play another, higher card in the same trick. The highest card
in the "lead" suit wins the trick. The winner of the trick leads for
the next trick, and so on until all cards are played. Tricks are scored
both during and after play. Players receive 1 point for leading a ten
or larger, 1 point for winning a trick, 2 points for winning the last
trick with a ten or higher, or 1 point for winning the last trick with
a nine or lower. After all tricks are played, each player counts the
number of tricks they have won. A player with seven through eleven tricks
receives 10 points; a player with all twelve tricks (known as a capet)
receives 60 points.
Repique and Pique
Players may also score points for preventing
the other player from scoring during a hand. A player gets a pique if she
reaches 30 points during the tricks, and the other player has no points.
A pique is worth 30 points. A player gets
a repique if she reaches 30 points during the first four parts of the
hand, and the other player has no points. A repique is worth 60 points.
Players must declare that they have a pique or repique, or else they do
not receive any points for them. 

Related Links:
The Middle Ages
The Black Plague
