There are a couple of organizations that govern the rules of snooker play. The official snooker rules are governed by the International Billiards and Snooker Federation (IBSF), which have been part of the Billiard Congress of America (BCA) rule book since 1993. The United States Snooker Association is part of the IBSF. Tournaments governed by the IBSF will use these rules, while rules governed by another organization called the World Professional Billiards and Snooker Association (WPBSA) abides by yet another set of rules (mainly in championship play).
When you see snooker on TV in other parts of the world, you will most likely be watching the WPBSA rules.
Even though the American and international official rules of snooker fall under the same organization (IBSF), there are still differences between the two different versions of the game. The rules differences are subtle, but significant.
Now that you have yet another cue sport under your belt … just go out there and show what you know!