Answer: The exact differentials are functions whose integration is nothing but the difference between values at the endpoints or limits.
For example, when the volume is integrated between two states V1 and V2, it equals the difference between V2 and V1.
But, in the case of the inexact differentials, the integration or differentiation is not straightforward subtraction between endpoints. For example, work transfer is a path function hence an inexact differential. Its integral over a process can not be a simple difference between values at the endpoints.
Rather,
Also, I would like to mention here about the cyclic integral of the Thermodynamic properties.
The properties are point functions and exact differentials hence when the cyclic integral is taken over the thermodynamic cycle the system goes back to the initial state hence the cyclic integral of the Thermodynamics properties is zero.
