Styrofoam is a good insulator because it traps pockets of air and other gases inside of it. Your fur or goose down coat keeps you warm in the winter because fur and feathers also trap air pockets. Wool and fiberglass also operate on this same principal, which is why wool socks are so effective, and why fiberglass is favored for insulating houses.
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Clothes in general trap air pockets, and this is why they are such good insulators. In the winter, the trapped air helps keep you warm. If the air weren't trapped, then it would move. The warm air that is heated by your body would leave to be replaced by colder air, and you would subsequently feel chilled.
Heat conduction also explains why a tile floor feels colder on bare feet than a rug or a wooden floor. The tile, wood, and rug are actually at the same temperature, but tile is a better conductor than either of them. It draws heat away from your foot more quickly than a wooden floor. The rug is even better, because it does not conduct heat away but rapidly warms up to the temperature of your foot.
What heat transfer process causes the water that you use to steam your vegetables to boil, or causes a radiator to heat your room? We will examine this in part three.
