In thermodynamics, one of the early things you learn is what steam tables are and why they are important.
The cliff notes are that simple problems look at the thermal change in a system where you're dealing with just a liquid or just a vapor. In thermodynamics, we're more interested in what's going on during the phase change from liquid to vapor.
That's where the steam tables come in. They show us the saturation pressure for a given temperature, or vice versa. For that condition, they show us the specific volume (which is the inverse of density), the enthalpy, and the entropy.
Here's a quick overview to how to use the steam tables: