The term 'INDOOR ROWING MACHINE, FOR SHORT' is abbreviated as ERG. An ERG is a type of indoor rowing machine that simulates the action of rowing a boat in water. It is used for exercise and training purposes, and is popular among athletes and fitness enthusiasts. The machine consists of a sliding seat, a flywheel, and a handle connected to a chain or cord. The user pulls the handle to move the seat back and forth, creating resistance from the flywheel. This resistance can be adjusted to increase or decrease the intensity of the workout.