Adding on to that- if your mass is the same( the cups are the same size) and you are putting in the same amount of liquid then it should be glass, but like the other person said it depends on different factors so don't take my word for it. Try doing an experiment to test it out.
styrofoam, but warning fammable and unsafe for the environment!
Metal - very good conductor of heat. Not a good insulator at all (Don't wrap cans in aluminum foil.) Glass - A little better resistor of heat energy transfer but still not great. Plastic - Depending on the exact material, plastic is probably your best bet. Especially if it's a foam of some sort; the air bubbles in the foam create barriers that heat energy has to cross to be able to escape.
aluminum foil
aluminum foil is better at blocking temperature from getting out than plastic wrap. the atoms in the element aluminum are bigger and have more neutrons/electrons and protons than the elements in plastic wrap.
paper
Styrofoam because it has a thick layer and is a good insulator.Paper and plastic are could alternatives but Styrofoam would work better, therefore glass would be the worst one to use because it would only keep it warm for a couple of minutes.
syrofoam
styraphoam
plastic is cheaper than some other materials and it keeps the fluid in it fresh
Glass bottles are easily washed because sometimes the debris will remain in the plastic bottles and as time goes by plastic bottles will become yellowish in color. The glass feeding bottles can be reused and it is restoreable. It is very safe when placed in dishwashers. It does not retain the smell of spoiled milk which is different in case of plastic. It keeps heat easily and may be kept warm in for longer periods and it does not pose health hazards to children. It ia also very easy to sterilize them because you can put them in boiling water.
It does not breathe. It keeps moisture in or out, the same with orders and oils. For this reason it is not so good for freezing.
A flask :)
I have found that brick cheese, such as Tillamook Cheddar cheese keeps better if wrapped in aluminum foil vs plastic wrap or a plastic baggie.
Foam container will keep it hotter. The air bubbles in the foam act as an insulator.
Glass keeps beer colder due to its molecular structure.
Glass because it is a poor conductor of heat. Aluminum is highly conductive, which means that when you pick it up the heat from your hand would move quickly through the aluminum and into your drink.
You unseal the glass from the plastic bezel it has an adesive wich keeps the two parts toghether, after you clean the glass you use a new adesive to seal the two parts back toghether.