Which mahjong is easiest to learn? +
Hong Kong — it has the clearest rules and the most forgiving scoring of the major styles, which is why we recommend it first.
Are the tiles the same across styles? +
Mostly. All three use the three suits, winds and dragons. American adds 8 jokers and treats the white dragon as a "soap"; Riichi adds red fives. The core tiles are identical.
If I learn one, can I play the others? +
Mostly. Hong Kong and Riichi share the same basic shape — four sets and a pair — so they transfer directly. American swaps that shape for a yearly card of set hands, but the tiles, the turn flow and the table skills all carry over.
Is "mahjong" the same as the solitaire matching game? +
No. This is the real four-player tile game. Mahjong solitaire is a single-player tile-matching puzzle that just borrows the tiles.