A ponnuki is worth thirty points

Ponnuki  

The proverb 'A Ponnuki in the center is worth thirty points' tells us that the ponnuki shape in this diagram is often very valuable.

Especially when played before middle game, a ponnuki in the center can exert influence in all directions. The number 30 here is of course just a manner of speaking - what is important is that it is large. One needs a very good reason to allow one's opponent to get one.

Tortoise shell  

Even better than the ponnuki is the tortoise shell in this diagram, where two stones have been captured.

By analogy with the ponnuki proverb, some say that this shape is worth 60 points. Again, one should not take this number too literally, but whatever the value of this position is, it is huge.

-- Andre Engels

A match between Aoki Kikuyo and Wang Chenxing, white made a Ponnuki in the center.