Pilsner is a type of pale lager. It takes its name from the city of Pilsen, Bohemia, in the Czech Republic.
Until the mid-1840s, most Bohemian beers were top-fermented. The taste and standards of quality often varied widely. The officials of Pilsen founded a city-owned brewery in 1839, called Bürger Brauerei, and  brewed beer according to the Bavarian style of brewing. Bavarian brewers had begun experiments with the storage of beer in cool caves using bottom-fermenting yeasts, which improved the beer's clarity and shelf-life. Josef Groll who, using new techniques and paler malts, presented his first batch of modern pilsner on 5 October 1842. The combination of pale colour from the new malts, Pilsen's remarkably soft water, Saaz noble hops from nearby Žatec and Bavarian-style lagering produced a clear, golden beer that was regarded as a sensation.
The Pilsner Brauart style of brewing was soon widely imitated. In 1859, “Pilsner Bier” was registered as a brand name at the Chamber of Commerce and Trade in Pilsen. In 1898, the Pilsner Urquell trade mark was created to put emphasis on being the original brewery.
The introduction to Germany of modern refrigeration by Carl von Linde in the late 19th century removed the need for caves in which to store the beer and thus allowed the brewing of bottom-fermenting beer in many places that had been unable to do so before.[4] However, even until recently the Pilsner Urquell brewery still fermented its beer using open barrels in the cellars underneath their brewery. This technology was changed in 1993 with the use of large cylindrical tanks; however, small samples are still brewed in a traditional way for taste comparisons. Pilsner also has the unique claim to being "the world's first golden beer".[5]
A modern pilsner has a very light, clear colour from pale to golden yellow, and a distinct hop aroma and flavour. Czech pilsners tend toward a lighter flavour (good examples being Pilsner Urquell and Staropramen), while those in a German style can be more bitter (particularly in the north, e.g. Jever) or even "earthy" in flavour. Distinctive examples of German pilsners are Aktienbrauerei Kaufbeuren Jubiläums Pils, Augustiner Pils, Beck's, Bitburger, Flensburger Pilsner, Fürstenberg, Henninger's Kaiser Pilsner, Holsten, König Pilsner, Königsbacher Pilsner, Pivara Tuzla Tuzlanski pilsner, Krombacher, Kulmbacher, Radeberger, Schwelm's Schwelmer Pils, Veltins, Warsteiner, Würzburger Hofbräu, and Wernesgrüner. On the other hand, Dutch (Amstel, Grolsch, Heineken) and Belgian pilsners (Jupiler, Stella Artois) have a slight sweet taste. Pilsners are identified by their participation in categories like "European-Style Pilsner" at the World Beer Cup or other similar competitions.
A pilsner is generally regarded as different from other pale lagers by a more prominent hop character, particularly from the use of Saaz noble hops and spring (soft) water. While pilsner is best defined in terms of its characteristics and heritage, the term is also used by some brewers (particularly in North America) to indicate their "premium" beer, whether or not it has a particular hop character.