An example of an adiabatic process is a piston working in a cylinder that is completely insulated. The cylinder does not lose any heat while the piston works because of the insulation.
In the adiabatic process, energy is transferred through work rather than heat. For example, when air or other gases are compressed, the gas becomes hot. The opposite is also true because gas cools when it expands quickly. However, the quick expansion or compression of gas is not completely adiabatic. Temperature changes do occur in an adiabatic process, but energy is not transferred outside of the system through that temperature change.