The classic jug is a cylindrical vessel with a handle, usually made of earthenware, ceramic, clay, tin or glass. Some jugs have a lid that is attached with a hinge above the handle, others are covered with a loose wooden lid or not at all. If the jug has a spout, it is called a jug and is not drunk directly from, but used to store liquids and pour them into glasses. Versions of today's jug were already used for drinking in ancient times. They were also used as storage and transport vessels because they protect the goods contained in them from light, insects and rodents as well as from water ingress. The practical jug has lasted for thousands of years and is still a basic item in most households today. Because we tend to store our food and liquids in glass or Tupperware these days, the jug only has a culinary use: it keeps our beer cool, protects it from wasps flying in, transports the barley juice conveniently to our mouths and makes the beer taste twice as good.
A very classic example comes from the Adler Bräu in Stettfeld, Franconia. Their version is made of stoneware and features the heraldic animal and the name of the brewery.