Is steel a insulator?
No, steel is neither a thermal (heat) nor electrical insulator
How do the different types of insulators affect the temperature of the can Out of Steel Wool Aluminum Foil Cotton and Bubble Wrap which one would be the best insulator?
An insulator does not conduct electricity or heat whatsoever. (Eg: Wood) A semi-conductor conducts electricity / heat but with imperfect efficiency. (Eg: Steel) A conductor is simply a term for something that is not an insulator. A super-conductor conducts heat and electricity with almost perfect efficiency.(Eg: Gold)