Self-propelled anti-tank gun

A tank destroyer or tank hunter is a type of armoured fighting vehicle, armed with a direct-fire artillery gun or missile launcher, with limited operational capacities and designed specifically to engage enemy tanks.

Tanks are armoured fighting vehicles designed for front-line combat, combining operational mobility and tactical offensive and defensive capabilities; tanks perform all primary tasks of the armoured troops. The tank destroyer on the other hand is specifically designed to take on enemy armour. Many are based on a tracked tank chassis, while others are wheeled.

Since World War II, gun-armed tank destroyers have fallen out of favor as armies have favored multirole main battle tanks. However, lightly armored anti-tank guided missile (ATGM) carriers are commonly used for supplementary long-range anti-tank work. The resurgence of expeditionary warfare in the past twenty years has seen the emergence of gun-armed wheeled vehicles, sometimes called "protected gun systems", which may bear a superficial resemblance to tank destroyers, but are employed as direct fire support units typically providing support in low-intensity operations such as the wars in Iraq and Afghanistan.

Dedicated anti-tank vehicles made their first major appearance in the Second World War as combatants developed effective armored vehicles and tactics. Some were little more than stopgap solutions, mounting an anti-tank gun on a tracked vehicle to give mobility, while others were more sophisticated designs. An example of the development of tank destroyer technology throughout the war are the Marder III and Jagdpanzer 38 vehicle, that were very different in spite of being based on the same chassis: Marder was straightforwardly an anti-tank gun on tracks whereas the Jagdpanzer 38 traded some firepower (its Pak 39, designed to operate within the confines of a fully armored fighting compartment, fires the same projectiles from a reduced propellant charge compared to Marder's Pak 40) for better armor protection and ease of concealment on the battlefield.

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