What phase of water is represented by saturated steam?

Saturated steam is the phase of water that occurs when water is in a gaseous state, specifically at the point where it is about to condense back into liquid water. In this state, the steam has reached an equilibrium where any additional heat would allow it to remain as a gas, while any decrease in temperature or pressure will begin to condense the steam back into liquid water. This phenomenon is characterized at the boiling point of water, where it can coexist in both liquid and vapor forms.

The other phases of water, such as semi-solid, liquid, and solid, do not describe saturated steam accurately. Semi-solid generally refers to a state that is neither fully liquid nor solid, which does not apply here. Liquid water is the state prior to vaporization, and solid refers to ice, which is far removed from the gaseous phase of saturated steam. Understanding the properties of saturated steam is crucial for applications in power engineering, as it is often involved in processes such as heating systems and turbines.