Winning Hands (Yaku)
One Han Yaku
Pinfu
Composed of a pair and 3 sets of tiles in sequence while waiting for the winning tile to complete the last sequence and has to be double side. Plus, there should be no melds (no chi/pung).
Tanyao
Composed only of simples (Chuu chan pai). This hand will still result in a one han even if the hand has chi or pon melds.
Riichi
A winning hand (yaku) that translates into a one han when the player is waiting for certain tiles (tenpai) and announces "riichi" without making any chi or pon melds. 1000 points are needed as the riichi charge.
Menzen Tsumo
A winning hand (yaku) that does not involve any chi or pon melds and the winning tile is drawn by the player.
Iipeikou
A winning hand (yaku) that is composed of 2 identical sequences in the same suit. Chi or pon melds invalidate this wining hand.
Two Han Yaku
Toitoi
A winning hand (yaku) that is composed of 4 sets of 3 identical tiles (kootsu) and a pair. Pon melds are allowed.
Sanshoku doujun
A winning hand (yaku) that is composed of sequences with the same numbers (7,8,9 for the example). Chi or pon melds convert this into a one han yaku.