Medium tanks fall between the Light and Heavy tanks. They are a mix of both, combining the high mobility of a Light tank and the armament of a Heavy.
Medium tanks can be deceivingly good. Medium tanks combine attributes from both Heavy Tanks and Light Tanks, usually keeping the best of both worlds. They're faster in mobility than Heavy tanks and better armed and armored than Light tanks. Medium tanks are best used offensively and are the most suited vehicles for Tank vs Tank combat. They can outgun light tanks and out maneuver heavy tanks. In dire situations, they can also be used as infantry support, notably, the Sherman Firefly, as it has access to HE and Smoke shells.