Comparison between work and heat - thermodynamics:

There are a number of similarities between heat and work.

1. Both heat and work are transient phenomena. The systems do not have heat or work. When a system undergoes some change, heat transfer or work done can occur.

2. The heat and work are boundary phenomena.  They are normally observed at the  boundary  of  system.

3. The heat and work signify energy crossing boundary of the system.

4. The heat and work are path functions and hence they are inexact differentials.

5. Heat and work are not properties of the system.

6. Heat transfer is energy interaction because of temperature difference only. All other energy interactions can be called as work transfer.

7. The magnitude of heat transfer or work transfer depends on the path followed by system during change of state.