The game known in Europe as Cadre has several variations

As in other carom games, America uses different terminology than in other parts of the worlld. We call it "balkline." The rest of the world calls it "cadre." Balkline games developed because players were too good at the championship game a form of straight rail where a triangular zone in the corners limited the number of points that one was permitted to make before moving the balls out of the zone. In balkline, the table is divided into either six or nine cadres (or zones) by drawing lines parallel to the long and short rails. The number of points a player can make while the two object balls are in the cadres is limited. See the different styles in the diagrams included here.

There are currently two cadre games, each with two variations. These are typically written: 47/1, 47/2, 71/1 and 71/2. The first number is the distance of the balkline from the rails in centimeters. The second number signifies the number of points that can be made with the two object balls in the cadre before one of the object balls must be driven out. In 47.1, for instance, the player must drive one of the object balls out of a cadre with the first point. Failure to do so ends the player's inning. In 47.2, the player may make a point when both balls are in the cadre but must drive one object ball out before making the second point. (An object ball driven out of balk that returns will reset a new count limitation.)

In 47.1 and 47.2, the table is divided into 9 cadres. In 71.1 and 71.2, the table is divided into six cadres. The games of 47/1 and 71/1 are generally considered harder than 47/2 and 71/2 because the player does not have the luxury of a set up shot before making the drive of an object ball out of balk. In America, you may sometimes hear players mention 18.1 or 18.2 balkline or even 28.1 or 28.2 balkline. These are equivalent to the European games, with the measurements expressed in inches rather than centimeters. (There are also some minor differences between the old American games and the current modern games, both in measurement and play.)

In today's tournament games, in addition to the balklines creating the cadres, there are also "anchor boxes" drawn on the table where the balklines meet the cushion. The anchor boxes limit the number of points that can be made within the anchor boxes. Without such a limitation, a good player would maneuver the balls where one object ball was in one box and the other was in the adjacent box and would score endlessly by keeping the balls in that basic position.

For the room player, however, the anchor boxes are not necessary. If anyone is inclined to play balkline, drawing the balklines without the anchor boxes will suffice. The lines can be drawn with tailor's chalk, which is really more a white wax, and a straight ruler.

Robert Bryne's Byrne's Wonderful World of Pool and Billiards contains a nice history of balkline. Willie Hoppe in his book, Billiards As it Should be Played, writes that one should not start playing balkline until one can make 100 points in straight rail. That might be sound advice.

REFEREE CALLS FOR BALKLINE
(a) "entrée" – both object balls are in the same balk. (all of the "entrée" calls, either alone or as part of the anchor calls below, are only used in 2-count limit games.)
(b) "dedans" – both object balls are in balk for the second time (in 2-count games) or for the first and final time (in 1-count games).
(c) "a cheval" – the object balls are on different sides of the line and free of count limitation. This call is only made when one or both object balls are near a balkline.
(d) "entree partout" – balls are in both the balk and the anchor for the first time.
(e) "entree dedans" – balls are in balk for the first time; in the anchor for the second time.
(f) "dedans entree" – balls are in balk for the second time, in the anchor for the first time)
(g) "dedans partout" – balls are in both the balk and the anchor for the second time
(h) "entree a cheval" – entree for the balk and one ball is just out of the anchor.
(i) "a cheval dedans" – balls are not in balk but are in the anchor for the second time.
(j) "a cheval partout" – balls are free of balk limit and the anchor.