A Kangaroo was a Canadian armoured personnel carrier (APC) during the Second World War which was created by converting a tank chassis. Kangaroos were created as an expedient measure "in the field" by the Canadian Army, and were so successful that they were used by other Commonwealth forces, including the British Army.
Their ability to manoeuvre in the field with tanks was a major advantage over earlier designs, and led to the dedicated APC designs that were introduced by almost all armies immediately after the war.
The Sherman M-4 Kangaroo was a conversion with a Sherman chassis topped with a personnel carrier that could transport 10 infantry. It was used primarily in Italy by the British Eighth Army.