What is the etiquette for discarding tiles in Chinese Mahjong?

Discarded tiles should be placed face-up in the center of the table in a clear, visible manner and announced verbally in many social games. Players should not discard too quickly; giving others a brief moment to see and potentially claim the tile is considered proper form. Once a discard is placed and the next player draws, the window to claim that discard is closed. It is also considered poor form to "fish," meaning to discard tiles in a pattern that hints at your hand and manipulates opponents into discarding what you need.