THE GAME OF MAHJONG
Just like any other game, the goal of playing is to win. In order to win in mahjong, your goal is to make a complete hand before your opponent can. A complete hand consists of 4 sets and a pair.

Initially at the start of each round, you and the opponent are each dealt 13 tiles. 99.99% of the time, the opening hand isn't a hand that you can actually win with. It is just a bunch of random tiles, some useful and some not. During each turn, you have the opportunity to draw a new tile and discard another. Turns alternate between you and the opponent. Fundamentally, you want to discard the useless tiles and keep the ones you need. Ultimately, your goal is to turn your hand of nothing into a complete hand that can win you the round. This is, for simplicity sake, how the game of mahjong works.

 
TILES
In mahjong there are a variety of different tiles available for play. Essentially 3 different types of tiles exist: numbers, winds, and dragons. There are 3 sets of numbered tiles that go from 1-9: characters, bamboos, and dots. There are also 4 different winds and 3 different dragons. A total of 34 different tiles and 4 sets of each, making a total of 136 tiles.

Character Tiles (MANZU):

First step in learning mahjong, memorize the characters. Numbers 1-3 isn't so bad but the others can be confusing if you've never seen them before. Play more, and you will eventually memorize it all. It isn't that difficult a task so don't worry.

Bamboo Tiles (SOUZU):

Note that the 1-bamboo tile is always a picture of a bird.

Dot Tiles (PINZU):

Numbered tiles 1 and 9 are known as Terminals. Numbers between 2 and 8 are known as Simples.

Wind Tiles:

The sequence above is: East, South, West, North.

Dragon Tiles:

The sequence above is: White Dragon, Green Dragon, Red Dragon. Much more easy to remember these than the winds since they are color coated.

Wind and Dragon tiles are known as Honors.

 
STARTING A ROUND
At the start of the match, a pair of dice is rolled. The roll of the dices determines who goes first. How it is determined varies from game to game. For some, each player rolls a pair of dice. Whoever has the highest number goes first. Sometimes a pair of dice is rolled only once. If the dices add up to an even number, the opponent goes first. If it adds up to an odd number, the player goes first. In real 4-player mahjong, it is considered a disadvantage to be first because as the starter, you are also the dealer. Payoff disfavors the dealer if anyone else wins. And the likelihood of someone else winning is pretty high. A 3 to 1 ratio basically. In 2-player video mahjong, it is only you against a single opponent. The starter is still the dealer but the disadvantage isn't as extreme as in real mahjong. In fact, I would say that it would be an advantage being the dealer, because you earn more points as dealer, than if not.

Each player has a wind associated with them depending on their seating position around the table. The starter or dealer is usually the East wind. The next player is the South, the third West, and the last North in a counterclockwise manner around the table. However, in video mahjong, there are only 2 players. In this case, the starter or dealer is the East wind and the other player at the opposite end of the table is the South wind. The prevailing wind of the round is the dealer's wind at the start of the match. However, wind association and prevailing wind may change during later rounds as the match progress.

Anyway, after the dices are rolled and the starter is determined, then the real game begins. Each player is distributed 13 tiles. Say you start first. The only thing you can do in the opening round is to draw a tile; well unless you have a Kong, but more on that later. To draw a new tile you press the N button. Now you have 14 tiles.

During your turn you can do a couple of things such as declare Reach, Pon, or Mahjong, but again, more on that later. Say you can't do anything, which is often the case. So in order to end your turn, you need to discard a tile to return your hand back to 13 tiles. Once you discarded a tile, your turn ends, and the opponent's turn begins. She will draw a tile and if she cannot do anything, she will discard a tile as well. Once discarded, her turn ends and the cycle starts all over again. Now it's your turn and the process is repeated as above until someone wins or if there are no more tiles left to be drawn, in which case there is a draw.

So basically one player draws a tile, and then discards a tile. The opponent does the same. The process is repeated over and over again until someone declares mahjong or all the tiles run out. It's that simple.

 
WHAT YOU CAN DO DURING A TURN
There are several different things that can be performed during each turn:
  1. You can draw a new tile (what you will be doing the majority of the time).
  2. You can declare Chi using the opponent's latest discarded tile.
  3. You can declare Pon using the opponent's latest discarded tile.
  4. You can declare Kong, using the opponent's latest discarded tile.
  5. You can declare Kong, once a new tile is drawn.
  6. You can declare Reach, once a new tile is drawn.
  7. You can declare Mahjong once a new tile is drawn or by using the opponent's latest discarded tile (In this case, you don't have to discard since you just won)
  8. You can discard a tile, once a new tile is drawn (what you will be doing the majority of the time).

Before I explain any further, I now need to explain what a mahjong is and what all these weird terms are.

 
WHAT EXACTLY IS A MAHJONG?
A mahjong is what is needed to win a round. It is a complete hand. A complete hand contains 4 sets and a pair. A set is a group of tiles. There are 3 types of sets:
  • Koutsu (Will refer to it as Pon)
  • Juntsu (Will refer to it as Chi)
  • Kantsu (Will refer to it as Kong)

* IMPORTANT. Throughout this site, I will refer to each set not by their actual names but by the names announced  when a player makes one of these sets using another player's discarded tile, which is Pon, Chi, and Kong. I do this in order to keep the terminology simple and also because most people are probably more familiar with these sets referred to by these names then by their actual names.

* Note that a set of tiles always contains one type of honor or one type of suit. There is no mixing of other suits for numbered tiles when forming a set.

A Pon is a group of 3 identical tiles. The group of 3 must be exactly the same tile. You cannot form a Pon of 3 tiles of the same number but of different suits. This is not considered a Pon. Here are some examples of what are Pons:

or or or

A Chi is a group of 3 sequential tiles of the same suit. Note that 8-9-1 and 9-1-2 combinations are not valid. Note also that Winds and Dragons cannot be use to make a Chi. Here are some examples:

or or   or

A Kong is a group of 4 identical tiles. The group of 4 must be exactly the same tile. You cannot form a Kong of 4 tiles of the same number but of different suits. This is not considered a Kong. Here are some examples of what are Kongs:

or or

A Pair is a group of 2 identical tiles. The group of 2 must be exactly the same tile. You cannot form a pair of 2 tiles of the same number but of different suits. This is not considered a pair. Here are some examples of what are pairs:

or or

Put them together and a mahjong is created. The 4 sets can be any combination of the 3 mentioned above. It can be all Pon, all Chi, all Kong, or simply a mixture of the three. A pair can be any pair as well. Here are some examples of a complete hand.

           

or

           

Note that if you have a Kong, you must announce that you do have one with the Kong button in order to draw another tile so you can still create a complete hand. More on this in the following section.

Also note that you cannot make a mahjong with just any hand that contains 4 sets and a pair. The hand needs to also be worth at least 1 Yaku. If not, then the hand is worthless and you cannot win with it. Yakus are explained in more detail in the Special Rules and Yaku section.

 
CONCEALED AND REVEALED SETS
Anytime when you play a card game versus other people, you want to make sure that the opponent does not see your hand in order to increase your chances of winning. You want to keep it a secret until the very end. The same applies to mahjong. You always want to have your hand concealed, so as to not let a win slip by. You never want to tell your opponent what you have. So in essence, a concealed set is a set that is not revealed to the opponent, until you mahjong. Yet there are certain times in the game where you must reveal certain parts of your hand in a given situation. One situation, of course, is if you get a mahjong and win. There are 4 other times that you must reveal it as well:
  1. If you declare Pon using the opponent's latest discarded tile.
  2. If you declare Chi using the opponent's latest discarded tile.
  3. If you declare Kong using the opponent's latest discarded tile.
  4. If you have a Kong in your hand.

I haven't mentioned this before, so I'll mention it right now. You can create a set using an opponent's discarded tile. You can only take it if you need that tile to complete an incomplete set that is missing only one tile. To declare Pon using an opponent's discard, for instances, you must, initially have 2 of the required tiles to complete the set. You cannot have just one of them.

However, you can only use the latest discarded tile that was just discarded to end the opponent's turn. Using an opponent's discard means that you cannot draw a tile for yourself during that turn as well. So if you have two 4-dot tiles for instances and the opponent just discarded a 4-dot tile, you can, if you want, declare Pon using the Pon button to complete that set. The same thing applies with Kong, except that you need 3 of the required 4 to make it.

Declaring a Pon, Chi, or Kong with an opponent's discard will cause that set to become a revealed set. When revealed, it is place away from your regular hand and faced up so the opponent can see. It looks something like this:

You can have a hand entirely of revealed sets. It's not good to do point-wise and can get you into a possible non-winnable situation but it can be done.

As stated above, if you have a concealed Kong in your hand, you must declare it to the opponent if you want to make it into a set. You must declare it in order to draw another tile again so that you can still complete your hand. Making a Kong will create a situation in which your hand now becomes one tile short, making it impossible to create a complete hand since there wouldn't be enough tiles in the hand to make one. Drawing a new tile makes up for the additional tile used to make the Kong. Think about it for a bit and you'll begin to understand why. Also, when you make a Kong, the new tile drawn is not drawn from the regular pile but from the dead pile.

Even though, the set is revealed to your opponent, it is still treated as if it was a concealed set. Below is a screen of what happens when you declare Kong:

The placement of the tiles may seem rather odd, but that's just how it is. Don't worry about it. As you can see from the screen, after the Kong was made, a new tile was drawn.

Another note is that if you have a revealed Pon in your hand, you still have the chance to make that Pon into a revealed Kong if the opportunity presents itself. Say that you have a revealed Pon of 7-bamboos. If you draw another 7-bamboo tile during one of your turns, you can declare Kong and change the revealed Pon into a revealed Kong. However, you cannot use an opponent's discard to change that Pon into a Kong. The reason being is that no sets can have more than 1 discarded tile from the opponent.

 
WHAT YOU CAN DO DURING A TURN (CONT.)
Here's a more detail outlook on what exactly you can do during a turn:

1. At the start of your turn, you can either:

  • Draw a new tile. Go to step 2.
  • Declare Mahjong (Ron) if the opponent's latest discard completes your hand. Round ends.
  • Use the opponent's latest discard to declare Chi. Go to step 2.
  • Use the opponent's latest discard to declare Pon. Go to step 2.
  • Use the opponent's latest discard to declare Kong. You will be able to draw a new tile after. Go to step 2.

2. After drawing a new tile or taking the opponent's discard, you now can do one of the following:

  • Declare Reach. You must discard the unneeded tile for Reach to take place. Turn ends.
  • Declare Mahjong (Tsumo) if the new tile drawn completes your hand. Round ends.
  • Declare Kong. You will be able to draw a new tile once more. Repeat step 2.
  • Discard a tile. Turn ends.

Now on to Reach.

Declaring Reach is not required to win. It is optional. One benefit of Reaching is to gain 1 Fan or a double in score in the end if you happen to win the round. A consequence of Reaching is that you become limited in what you can and cannot discard.

You can only declare Reach when you need only one more tile to go out. The expression "to go out" is just another way of saying  "to declare mahjong". I use this expression quite often in the other sections, mainly, for convenience. Plus, it sounds much nicer. Also, you can only declare Reach if your hand is entirely concealed. You cannot declare it if you have any revealed sets in your hand.

Reach can be declared after you have drawn a new tile. When you declare Reach, a tile needs to be discarded. The remaining tiles left needs to be a hand where the addition of another tile will allow you to go out. Also when you declare it, a Reach stick is place on your side of the table. The significance of the stick is discussed further in the scoring section. The stick looks like a long white stick, with a dot in the middle. A picture of it can be seen from the image above in the previous section.

The tiles that are in your hand after Reach is made can no longer be discarded during later turns. You can only discard the newly drawn tile during each turn there after.

Also, after you declare Reach, you are still able to change any Pon in your hand into a Kong if the tile needed is drawn by you

Declaring Mahjong is to win the round. You can declare mahjong once you make a complete hand. You can go out two different ways. You can go out with a drawn tile that is drawn by you or you can go out with the opponent's latest discarded tile. Declaring mahjong with a drawn tile is called Tsumo. Declaring mahjong using the opponent's latest discard is called Ron.

 
ENDING A ROUND
Two situations can occur at the end of a round. The first is if someone declares mahjong. In this case that person wins the round. On the other hand, if no one goes out, and there are no more tiles to be drawn, the round ends up in a tie and points may or may not be rewarding for certain players. Usually the round ends after each player has drawn and discarded 18 tiles.

Let's say, for example, that at the end of the round, your hand requires only one more tile to go out, while the opponent needs two or more. In this case, you have Tenpai, while the opponent has No-Ten. Neither hand is scored since they are incomplete. However, you are rewarded a certain amount of points, while the opponent gets her score deducted by the amount you gained. The same can occur the other way around. But, if neither of you has a hand in which you need one more tile to go out, No-Ten for both, then no points are rewarded to anyone and a new round begins. If both you and the opponent have Tenpai, it remains scoreless as well.

 
WINNING A MATCH
Declaring Mahjong wins you the round. But in order to win the match, defeat the opponent and move to the next, you often need to win either a series of rounds or eliminate them point-wise. Some games require you to win a certain amount of rounds to move on. Others require you to eliminate them point-wise. Most mahjong games implement both. Whichever of the two you do first wins you the match.

Games requiring you to win a series of rounds to advance to the next opponent usually require you to win 3 to 5 rounds. For many games, the opponent strips one article of clothing for each round you win. The opponent loses the match when she cannot strip no more. You lose if you lose a certain amount of rounds as well.

Other games require you to win by points. Both you and the opponent first start out with an initial amount of points. When someone wins the round, their hand is scored depending on how good the hand is. Those points are added to the winner's score and deducted from the loser's. Whoever's score reaches zero first loses the match.