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Carom billiards, of any variety, requires two people. It can be played with a third, but standard carom is with two. You'll need your standard billiards table -- 4 feet (1.2 m) by 8 feet (2.4 m), 4 1⁄2 feet (1.4 m) by 9 feet (2.7 m), 5 feet (1.5 m) by 10 feet (3.0 m), or 6 feet (1.8 m) by 12 feet (3.7 m) without pockets. This "without" pockets thing is pretty important. You could play on a pool table (pocket billiards), but you'll soon find that the pockets get in the way and could potentially ruin the game. Here's everything you need to know (and some things you may not) when it comes to the table:  Those diamonds are for you to use! If you know your geometry, you can use them to aim your shot. We'll cover that in the next section (strategy). The rail by where the first player breaks is called the short, or head, rail. The opposite rail is called the foot rail, and the long rails are called the side rails. The area behind which you break, behind the "head string," is called the "kitchen."  The pros play on heated billiards tables. The heat gets the balls to roll more smoothly. It's green so you can look at it for long periods of time. Apparently humans can handle green better than any other color. " That's where you each line up your ball near the baulk cushion (the short end of the table where you break from), hit the ball, and see who can return it closest to the Baulk cushion as the ball slows to a stop. The game hasn't even started yet and it takes skill! If you hit the other player's ball, you forfeit your chance of calling who starts. If you do win the lag, it's generally accepted that you go second. The player who breaks generally wastes their turn setting up the balls, not taking a strategic shot. You'll each need a cue stick, for starters (you had these for the lag, right?). Billiards cues are actually shorter and lighter than their pool counterparts, with a shorter ferrule (the white part near the end) and a thicker butt. Then you'll need three balls -- one white cue ball (heretofore called "white"), one white cue ball with a black spot on it ("spot"), and one object ball, typically red. Sometimes a yellow ball is used in place of the spot. The person who wins the lag calls which ball they'd like to be theirs (cue ball), the white or the spot. It's just a matter of personal preference. The object ball (red) is then placed at the foot spot. That's where the point of the triangle would be in pool, by the way. The opponent's cue ball is placed at the head spot, where you normally break from in pool as well. The starting player's cue is then placed on the head string (in line with the head spot), at least 6 inches (15 cm) from their opponent's cue. So, obviously, when your ball is in line with your opponent's, it's very hard to hit both balls on the table. Hence why if you win the lag, you opt to go second. As with any game that's centuries old, there are variations in play. Some make it easy, some make it hard, and some make it faster or slower. How much time do you have on your hands? And how much skill?  For starters, every type of carom billiards involves getting a point by striking both balls on the table. It's how you do that that changes:  In straight-rail billiards, as long as you hit both balls, you get a point. This is easiest. In one-cushion billiards, you must hit one cushion (one side of the table) before the second ball is displaced. In three-cushion billiards, you must hit three cushions before the balls roll to a stop. Balkline billiards removes the one flaw in this game. If you manage to get both balls into a corner, you could, presumably, hit them off of each other over and over and over. Balkline billiards stipulates that you cannot receive points from a shot where the balls are in the same area (often the table is divided into 8 sections) of the table.   Once you determine how you get points, decide at what point you'd like to stop. In one-cushion, that number is generally 8. But three-cushion is so hard, you'll have better luck with 2! Move your arm smoothly back, then forward in a pendulum motion. The rest of your body should remain still as you stroke through the cue ball, letting the cue come to rest naturally. There you have it -- all you gotta do is hit both balls to receive a point -- technically, each turn is referred to as a "cannon." But here are some more specifics:  The player who goes first must hit the red ball (it'd be weird to hit the other, anyway) If you score a point, continue shooting Playing "slop" (accidentally getting a point) is generally regarded as illegal Always keep one foot on the floor at all times "Jumping" the ball is a foul, as is hitting a ball when it's still in motion You can do this while taking your practice strokes. Line up your cue stick with where you would hit the ball if you could hit it directly. Then aim for that spot. Most often, you'll want to hit the cue ball squarely in the center. Sometimes, you may want to hit the ball to one side or another to impart sidespin, or "English," to it to make the ball travel to one side. Occasionally, you may want to hit the cue ball below center to cause it to climb over a ball you don't want to move and strike a ball you do want to move.

Summary:
Grab a partner and a billiards table. Determine who goes first by "lagging. Set up the game. Determine the rules you and your partner want to play by. Play the game! Look for the place on the cue ball where the cue tip should connect.