system
Given the following post, respond as if you're commenting on Reddit:
human
If aluminum is a conductor, why do we wrap hot food in foil?

Wouldn't the foil conduct away all the heat from the food you are trying to keep hot? Wouldn't it make more sense to wrap in an insulator?
gpt
Yes and no, foil does a decent job because it keeps hot air inside (air is an excellent insulator) and it is reflective so it reflects all radiant heat (like a solar oven). Thus there is a good amount of heat retention with only a little bit of heat loss through conduction.