As mysterious as they look, stouts are typically dark brown to pitch black in color. A common profile amongst Stouts, but not in all cases, is the use of roasted barley (unmalted barley that is kilned to the point of being charred) which lends a dry character to the beer as well as a huge roasted flavor that can range from burnt to coffee to chocolate. A different balance of hops is up to the brewers preference, but the roasted character must be there.
Average alcohol by volume (abv) range: 4.0-7.0% --BeerAdvocate