Beginner's Lesson 4
Taatsu and Basic Tile Efficiency
We have learned about sequences, triplets, pairs, and how to compose a winning hand. Now, we are going to cover how to make sequences efficiently.  
Here are some tiles, 1 through 9.
Since 1s and 9s are terminal tiles and do not loop around, their usefulness is limited even among number tiles.  Let’s count how many different sequences we can make with each number tile.
As you can see by the table, 1s and 9s can only be used in one type of sequence and therefore have the lowest score. Conversely, 3s, 4s, 5s, 6s, and 7s can be used in three types of sequences each and have the highest score. The 2s and 8s are in the middle.
Next, let’s take a look at the types of taatsu (2-tile combinations) that can be used to make a sequence.

You may have noticed that the in the examples 12 and 24 are waiting for the same 3, but they have different names. This is because the shape of the taatsu is slightly different. Neither are complete sequences, but 24 has a chance to change into a ryanmen wait by drawing a 5 to switch out with the 2. However, a penchan does not have this benefit. This makes a kanchan better than a penchan.


By the way, there is one other taatsu that is not included in the table. That would be a pair (toitsu). A pair can accept a third tile of itself to become a triplet.


In the next lesson, we’ll use live tiles to play mini games!

Beginner's Lessons 15
Beginner's Lessons 16
Beginner's Lessons 17
Beginner's Lessons 18
Beginner's Lessons 21
Beginner's Lessons 22
Beginner's Lessons 19
Beginner's Lessons 20
Beginner's Lessons 23
Beginner's Lessons 24