Point and Path Function - Thermodynamics:
Point Function
A point function is single valued function which always possesses a single - value is all states. For instance each of the thermodynamics properties has single - value in equilibrium and other states. These properties are called as point function or state function.
Or
When the two properties locate a point on graph (coordinates axes) then those properties are known as point function.Such as pressure, volume, enthalpy, internal energy.
Path Function
Those properties, which cannot be located on graph by a point but are given by area or show on the graph.
A path function is different from point function. It depends on nature of process that can follow different paths between same states. For example work, heat, heat transfer.