The triple point of water is the condition at which:

1. The triple point is a single, uniquely defined set of conditions of temperature and pressure. 2. At that point the solid, liquid and vapour states of the substance all coexist in equilibrium. 3. Because it is unique and reproducible, it serves as a fixed point for temperature scales. 4. Describing it as heating water from 0°C to 100°C was a recorded answer and confuses it with the range between the ice and steam points. 5. It is a separate idea from a thermometric property, which is a physical property varying linearly and continuously with temperature. _Source: NECTA ACSEE 2023 Physics 131/1, Question 5:Heat (Thermometers and First law of Thermodynamics)_