Beer
beer is an alcoholic drink made by fermenting starch sugars from barley and malt. Other ingredients are water, hops and yeast.
Is beer vegan? It's not easy to answer.
Many beers are filtered with isinglass, Gelatin, Glycerin or Casein. It is worth nothing, that this process is more common in Europe.
Stout
A Stout is a dark, top-fermented beer.
Unless it says it is a milk stout, it could be vegan.