The Panzer I is a light tank which was produced in Germany in the 1930s.it had two 7.63mm millimetre machineguns. The name is short for the German Panzerkampfwagen I (armored fighting vehicle mark I), abbreviated PzKpfw I. The tank's official German ordnance inventory designation was SdKfz 101. Design of the Panzer I began in 1932 and mass production in 1934. Although intended only as a training tank to introduce the concept of armored warfare to the German Army, the Panzer I saw combat in Spain during the Spanish Civil War, in Poland, France, Soviet Union and North Africa during the Second World War, and even in China during the Second Sino-Japanese War. Based on experience gathered during the Spanish Civil War, the Panzer I helped shape the German armored corps used to invade Poland in 1939 and France in 1940. By 1941, Panzer I chassis were being reused for production of tank destroyers and assault guns. There were attempts to upgrade the Panzer I throughout its service history, including by foreign nations to increase its lifespan. It continued to serve in the armed forces of Spain until 1954.