When it comes to dart games, there are lots to choose from. 501 and its little brother 301 are probably the most played games along with cricket. There are different rule variations for these games as well, depending where you are in the world. One of the variations for cricket is extended cricket or Moose as its sometimes called where you have to get a treble , a double and 3 in a bed as well as the normal 20 thru 15 and the bull. (Remember local rules take precedent over national rules, at least if you want to avoid an argument that is). Also there are team games like doubles where there are 2 people in each team etc. There are also more wacky dart games to play such as Shangai, Baseball and round the clock etc. which are more fun for the average player. To start with lets look at the standard games.
Lets start with the game of Cricket; The cricket scoring board is marked as follows, 20, 19, 18, 17, 16, 15, B: The B on the card signifies the Bull. To score points in the game you have to hit each number 3 times (1 treble will do nicely) and then that number is marked by an O meaning that number is "Open" for you to score on and each time you hit that number you score that amount of points with the doubles and trebles counting as 2 x and 3 x the number value as normal. Your opponent however can stop you from scoring any more by also registering 3 hits on your number; the number is then marked with an X and takes no further part in the game. If you hit the number 20 5 times the number 20 is then open for you to score after 3 hits and you have scored 40 towards your total, indicated by an O by your name. When the other player also hits the 20 3 times the number 20 is closed, indicated by an X, and it is no longer available to score points with by either player, and game moves on to the other numbers. To win the game you must get more points than the other player and hit every number and Bull 3 times. (The centre bull is counted as a double and the outer bull a single) It can get very tricky to decide if you go for points or close out your opponents scoring numbers.
The game of 501 is one of the simplest games to play and is the game played in all the big money professional tournaments. Basically you start with a score of 501 and the object is to get down to a score of 0 by deducting your score from the 501 total. The finishing dart to the game must land in the double ring, (obviously corresponding to your score and so be an even number of 40 or smaller). The bust rule means that if you score more than you need or just one less than you need then you are "bust" and the score is voided for that turn. You start the next turn with the same score you had before. The dreaded scenario is to end up on double 1 and keep missing it. The double one finish is often called "Annie's House" for reasons lost in the mists of time.
This is basically a shorter version of 501, the difference being, most local rules dictate that you must start your scoring with a double as well as finish on a double.
These are just the basic dart games, as I've indicated there are lots more, but if you know these universal games you will be able to play darts with someone wherever you are in the world.