Lagers are brewed with "bottom-fermenting" yeasts at much colder
     temperatures, 35-50F (2-10C) over long periods of time (months). This
     is called "lagering". Lagers include bocks, doppelbocks, Munich- and
     Vienna-style, Maerzen/Oktoberfest, and the famous pilsners. Pilsner
     beer originated in the town of Pilsen, now in the Czech Republic and
     was the first non-cloudy beer. Most popular beers produced by the
     large North American breweries were originally of the pilsner style.
     These have diverged a great deal from the original style and succeed
     now by the force of the mass-marketing prowess of the brewers rather
     than any remarkable qualities of the beers themselves.