heavy tank

heavily armored combat tank with a large cannon

Tanks can be classified in a variety of ways: usually either by intended role, or by weight. Modern tank designs have favoured a "universal" design that has generally eliminated these sorts of classifications from modern terminology, which tends to refer to almost all designs as main battle tanks.The most common division in the role has been between tanks intended to focus on fighting either with or against infantry, and tanks intended for fighting against other AFVs, especially other tanks. The British referred to these as infantry tanks and cruiser tanks respectively, although the latter was expected to exploit holes in the enemy lines and "cruise" at high speeds behind the lines. Other specialist roles include anti-tank vehicles or tank destroyers which are generally highly armored compared to similar generation multi-purpose tanks, and assault guns that mount oversized and typically low-velocity guns, for attacking fortifications.
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