air conditioning is a transfer of heat. a liquid evaporates and absorbs heat from the air around it(your living space) and then is condensed and pumped around to a different heat exchanger (condensor) outside where air removes the heat. a rather simple way of putting it.

Fit 03 is right. the difference between a refrigerator and an air conditioner is that a refrigerator cools an interior space, and releases heat to the surroundings; but an air conditioner cools ambient space, and releases heat outdoors.

babthrower - I can't see the difference you have indicated!. Surely an refrigerator and a room in your example are the same thing on bigger scales!. The refrigerator is just a small room in a big room, as a room is just a small room in a big world!