Lagers are produced with bottom-fermenting Saccharomyces uvarum (a.k.a. S. carlsbergensis) strains of yeast at colder fermentation temperatures than ales. This cooler environment inhibits the natural production of esters and other fermentation byproducts, creating a "cleaner-tasting" product.

The following beers are fermented or aged with mixed traditions. They can be brewed as an ale or lager (including unusual ingredients) or be made using unusual techniques or procedures.