Water at atmospheric pressure at sea level boils at 100 degrees Celsius or 212 degrees Fahrneheit. That is it's 'boiling point'.
If the water is put under pressure, higher than atmospheric pressure, it boils at a higher temperature.
If the pressure is decreased below sea level atmospheric pressure, it boils at a lower temperature.
Therefore, raising pressure above atmospheric pressure increases the boiling point. Lowering it below atmospheric pressure lowers the boiling point.
Changing water pressure changes the temperature at which it boils.
