The process of heating or cooling of a gas is defined as a thermodynamic process. It has been observed that during a thermodynamic process, change takes place in various properties of the gas such as pressure, volume, temperature, specific energy, specific enthalpy etc. The following thermodynamic processes are important:

1. Constant volume process or isochoric process
2. Constant Pressure Process or Isobaric Process
3. Hyperbolic process
4. Constant temperature process or isothermal process
5. Adiabatic process or isentropic process
6. Polytropic process
7. Free expansion (or unresisted expansion) process
8. Throttling process