What is an adiabatic process and where does it occur?

An adiabatic process occurs without any heat transfer between the system and surroundings, where Q = 0. The work done results entirely from changes in internal energy. Practical examples include rapid compression in IC engines, expansion in turbines, and flow through well-insulated devices. For ideal gases, adiabatic processes follow the relation PV^γ = constant, where γ is the specific heat ratio.