Meet the tiles
Taiwanese mahjong uses 144 tiles. That sounds like a lot, but they fall into just four kinds: the numbered tiles, the winds, the dragons, and the flowers.
The numbered suits are Characters (萬), Dots (筒) and Bamboo (索), each running 1 to 9, with four copies of every tile. Between them they make up most of the tiles on the table.
Characters (萬), 1 through 9.
The winds are East, South, West and North (東南西北); the dragons are Red, Green and White (中發白), four copies of each. Together these seven are the honor tiles (字牌). They carry no number, so they only ever group with tiles identical to themselves.
The four winds: East, South, West, North (東南西北).
The three dragons: Red, Green, White (中發白).
There are eight flowers: 梅蘭竹菊 and 春夏秋冬. A flower is not part of your hand — when you draw one you turn it face up in front of you and draw a replacement.
All eight flowers: 梅蘭竹菊 and 春夏秋冬.
108 numbered tiles, 28 honors, 8 flowers: 144 in all.