Sauerkraut is finely shredded cabbage that has been fermented by various lactic acid bacteria, including Leuconostoc, Lactobacillus, and Pediococcus. It has a long shelf-life and a distinctive sour flavor, both of which result from the lactic acid that forms when the bacteria ferment the sugars in the cabbage. It is therefore not to be confused with coleslaw, which receives its acidic taste from vinegar.
The word comes directly from the German language, which literally translates to "sour cabbage". Sauerkraut is traditional in German, Austrian, Slovenian, Croatian (kiseli kupus), Slovak (kyslá kapusta), Polish (kiszona kapusta), Czech (kysané zelí), Dutch (zuurkool), Estonian (hapukapsas), Latvian (skābi kāposti), Lithuanian (rauginti kopūstai), Danish and Norwegian (surkål), Romanian (varza murata), Serbian, Bulgarian (кисело зеле kiselo zele), Russian (квашеная капуста), Ukrainian, Hungarian (savanyú káposzta), and Belarusian cuisines. It is also part of the native cuisine of Friuli-Venezia Giulia and Trentino (capuzi garbi and crauti) in Northern Italy, and Alsace Lorraine in North Eastern France (choucroute). Finally, it is also popular in many parts of Northeast and Northern China, the USA, Chile (chucrut), and Canada.