History As a sport Equipment Major games List of cue sports and games

Games played on a carom billiards table[edit]
Main article: Carom billiards
Straight rail[edit]
Main article: straight rail
In straight rail, a player scores a point and may continue shooting each time his cue ball makes contact with both other balls. Some of the best players of straight billiards developed the skill to gather the balls in a corner or along the same rail for the purpose of playing a series of nurse shots to score a seemingly limitless number of points.
The first straight rail professional tournament was held in 1879 where Jacob Schaefer Sr. scored 690 points in a single turn^{[11][page needed]} (that is, 690 separate strokes without a miss). With the balls repetitively hit and barely moving in endless "nursing", there was little for the fans to watch.
Balkline[edit]
Main article: Balkline
In light of these skill developments in straight rail, the game of balkline soon developed to make it impossible for a player to keep the balls gathered in one part of the table for long, greatly limiting the effectiveness of nurse shots. A balkline is a line parallel to one end of a billiards table. In the game of balkline, the players have to drive at least one object ball past a balkline parallel to each rail after a specified number of points have been scored.
Cushion billiards[edit]
Main articles: one-cushion caroms and three-cushion billiards
Another solution was to require a player's cue ball to make contact with the rail cushions in the process of contacting the other balls. This in turn saw the three-cushion version emerge, where the cue ball must make three separate cushion contacts during a shot. This is difficult enough that even the best players can only manage to average one to two points per turn. This is sometimes described as "hardest to learn" and "require most skill" of all billiards.

Man playing billiards with a cue and a woman with mace, from an illustration appearing in Michael Phelan's 1859 book, The Game of Billiards.