The Tiger I was a German heavy tank of World War II. The tank was classified with ordnance inventory designation Sd.Kfz.182 and initial designation was Panzerkampfwagen VI Ausführung H (literally "armoured combat vehicle VI version H", abbreviated PzKpfw VI Ausf. H) where 'H' denoted Henschel as the designer/manufacturer. Although the general design and layout were broadly similar to the previous medium tank, the Panzer IV, the Tiger weighed more than twice as much. This was due to its substantially thicker armour, the larger main gun, greater volume of fuel and ammunition storage, larger engine, and a more solidly built transmission and suspension. At over 50 tonnes dead weight, the suspension, gearboxes, and other such items had clearly reached their design limits and breakdowns were frequent if regular maintenance was not undertaken.

The Tiger was still at the prototype stage when it was first hurried into service. It was introduced beginning in 1943 in North Africa and in the Soviet Union and therefore changes both large and small were made throughout the production run. A redesigned turret with a lower cupola was the most significant change. To cut costs, the river-fording submersion capability and an external air-filtration system were later dropped. The tank was usually deployed in independent heavy tank battalions. It gave the German Army its first armoured fighting vehicle that mounted the mighty 8.8 cm KwK gun (derived from the 8.8 cm Flak 36).


While the Tiger I has been called an outstanding design for its time, it has also been called over-engineered, using expensive materials and labour-intensive production methods. The Tiger was prone to certain types of track failures and breakdowns and was limited in range by its high fuel consumption. It was expensive to maintain, but generally mechanically reliable. It was difficult to transport and vulnerable to immobilisation when mud, ice, and snow froze between its overlapping and interleaved Schachtellaufwerk-pattern road wheels, often jamming them solid. This was a problem on the Eastern Front in the muddy rasputitsa season and during periods of extreme cold.


The tank was given its nickname "Tiger" by Ferdinand Porsche, and the Roman numeral was added after the Tiger II entered production. 

The main problem with the Tiger was that its production required considerable resources in terms of manpower and material, which led to it being expensive: the Tiger I cost over twice as much as a Panzer IV and four times as much as a StuG III assault gun. Partly because of their high cost, only 1,347 Tiger I and 492 Tiger II tanks were produced. The closest counterpart to the Tiger from the United States was the M26 Pershing (around 200 deployed in Europe (ETO) and the IS - 2 from the USSR (about 3,800 built during the conflict).


From a technical point of view it was superior to its contemporaries, and despite the low number produced, shortages in qualified crew and the considerable fuel requirement in a context of ever shrinking resources, Tiger tanks had a large impact in the war with Tigers (including Tiger IIs) destroying at least 10,300 enemy tanks, and 11,380 AT guns and artillery pieces in WW2. This was achieved for the loss of 1,725 Tigers whereby most losses were caused by abandoned, broken down, etc. vehicles.