In poker, ICM refers exclusively to tournaments. It is an abbreviation for the Independent Chip Model, a system that assigns monetary value to tournament chips.
In cash games, every chip has its face value, and there is no need for any special calculations. In tournaments, however, you only get paid based on the position you finish in and can only ever get a portion of the entire prize pool.
ICM takes into account the entire prize pool, the number of players left in the tournament, the total number of chips in play, blinds, and pay jumps to determine your chip stack’s value at any given point.
This concept is very important when players are at the final table and discussing a deal, as it provides a better money distribution system than the previously used chip-chop approach, which only considers stack sizes. Learn more about ICM poker.