In the US, denatured alcohol is not methanol; it's ethanol
with a denaturant. The denaturant can be methanol, or
a number of other chemicals, as long as it's sufficiently
adulterated to prevent a person from using it for ingestion.

"using it for ingestion" = "drinking it" You will soon be visited by
Jacques Barzun and put to death in a most unpleasant manner.

Methanol is wood alcohol. It _is_ drinkable -- but poisonous. Among other
things, it causes blindness.

I've never tasted denatured alcohol -- a few drops are harmless -- so I
don't understand why denatured alcohol is "undrinkable".