Quark or quarg is a type of fresh dairy product made from milk. The milk is soured, usually by adding lactic acid bacteria cultures, and strained once the desired curdling is achieved. It can be classified as fresh acid-set cheese. Traditional quark can be made without rennet, but in modern dairies small quantities of rennet are typically added. It is soft, white and unaged, and usually has no salt added. It is traditional in the cuisines of Baltic, Germanic and Slavic-speaking countries.
Dictionaries sometimes translate it as curd cheese, cottage cheese, farmer cheese or junket. In Germany, quark and cottage cheese are considered to be different types of fresh cheese and quark is often not considered cheese at all, while in Eastern Europe cottage cheese is usually viewed as a type of quark (e.g. Russian for cottage cheese is "зернёный творог" zernyony tvorog, literally "grainy quark"). In Austria, it is called topfen.
Quark is similar to French fromage blanc. It is distinct from Italian ricotta because ricotta (Italian "recooked") is made from scalded whey. Quark is somewhat similar to yogurt cheeses such as the South Asian chak(k)a, the Arabic labneh, and the Central Asian suzma or kashk, but while these products are obtained by straining yogurt (milk fermented with thermophile bacteria), quark is made from soured milk fermented with mesophile bacteria.