Chow — three sequentially-numbered tiles of the same suit (3.4.12); Pung — three identical tiles, concealed or melded (3.4.13); Kong — an exposure of four identical tiles; also the meld itself (3.4.19)
Why people argue about this
People often assume that a Pung in Mahjong MCR (WMO) can be any three tiles of the same suit, including those with different values like 3, 5, and 7 of a suit instead of needing them to be sequentially numbered as per the rule. The confusion arises because they overlook the specific detail about sequential numbering required for a Pung to count.
