A drum (from French bidon) is an airtight container used to contain, transport and store liquids.

It is, essentially, a container with a built-in handle and a flat bottom, of different shapes and materials; It was born as a rectangular prismatic sheet metal container, but currently the most used material is plastic. It can also be made of cardboard or plywood and its shape, in addition to the usual prismatic, cylindrical or triangular. Its capacity exceeds that of a bottle but does not reach that of a barrel.

The first portable hermetic containers for fuel and water were invented by the Germans before the start of World War II, under the name Wehrmachtskanister, with a capacity of 20 liters. It was a metal container, and therefore resistant to shocks, with such a capacity that it required a handle for transport.

Before the appearance of the drum, prismatic cans with a triangular base were used, easy to deposit and support, but without a sufficiently resistant structure. In 1935, the German army held a competition to supply fuel containers, from which the model developed by the company Mueller Co Ltd in Schwelm, Westphalia, under the direction of Vicente Grünvogel, was chosen. In 1936, a series of 5,000 units reached the troops as a test. The final model, approved by general order (AHM) No. 324 of July 8, 1937, received its final form by the company Ambi-Budd (ABP). It included an incised relief on its wider faces, usually in the shape of a cross, which reinforced the metal structure. Later models with better profiles were manufactured for the German Wehrmacht and Waffen SS from 1939 to 1945 by 19 manufacturers in large quantities, and included a built-in funnel. From 1940 there was also a 20 liter water unit container.

It was used by the German Wehrmacht in almost all European and North African theaters of World War II. It was also used by Switzerland and Italy during the war. During the course of the war, the British and Americans were struck by the excellent design of the container and began to manufacture it under the name Jerry can, alluding to the derogatory form used by the British to name the Germans: Gerrys or Jerrys from the English germans. Later it was incorporated by the British army and from this it passed to the American one. With the landing of the Allies in July 1944, large quantities of containers entered the European continent, with capacities from 2.5 to 20 liters, quickly becoming adopted for civilian use as well.

The British containers were marked with the letters B and D, for War Department, which later led to its French name, bidon; From this comes, in turn, the Spanish term canister.

Later their use extended to industry and agrochemicals, and they continue to be produced in large quantities in many countries.