Under 1 atmospheric pressure(1 atm) ,the boiling point of water is 100 degree C and it becomes steam.Therefore,the maximum temperature of water at 1 atmospheric pressure is 100 degree C.
If the pressure is altered,the boiling point of water varies(increase or decrease).
2007-01-20 12:41:18 補充:
Both steam(gas state of water) and water(liquid state) can be at 100 degree C.