That's for pure water at one bar of pressure, of course. Changes in pressure, and impurities in the water, can cause the freezing point to change - a well-known example being that the addition of ordinary salt causes the freezing point to drop.
32 degrees for pure water. In Celcius, zero degrees is the freezing temperature of pure water and 100 is its boiling point. In Farenheit, zero is the freezing point of SEA water, and 100 was to be the temperature of the human body. That temperature was a bit off, so normal body temperature is 98.6 instead of the planned 100. At -40, celcius and farenheit are the same value.