The process by which heat moves through air or liquid is called

Convection

Explanation:

Three methods of heat transfer they are conduction, convection, and radiation.

The conduction heat transfer take places in the solid materials.

Convection heat transfer take place in the moving fluid like air, water etc.

Radiation heat transfer take place in the form of electromagnetic waves. Every body which have temperature above absolute zero, emits radiation.

Therefore the answer is - -

Convection