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Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Difference between isopropyl alcohol ("rubbing alcohol"), ethyl alcohol, and methyl alcohol?

Edit: Thanks guys.
gpt
Ethyl alcohol is the kind you drink. It is produced by yeast. . The yeast eat some kind of sugar or starch and turn it into carbon dioxide and alcohol. In wine the process is pretty simple – yeast eats the sugar in grape juice and creates alcohol. In whiskey, the alcohol is distilled to get the concentration higher.

Ethanol that you purchase as a car fuel is the same kind of alcohol found in whiskey, but it has been distilled to the point where it is nearly pure alcohol (as opposed to whiskey which is typically only 40% alcohol and 60% water).

Methanol is sometimes found in windshield wiper fluid to keep it from freezing, and it is also used as the fuel for Champ cars and Indy cars. It is sometimes called wood alcohol because it used to be made from wood, but today its made from natural gas. Methanol is poisonous, and it is one of the chemicals that can be used to poison denatured alcohol. 

The chemical difference is how many carbon atoms there are.