Blitzkrieg: A German war doctrine in using tanks, airplanes, and infantry to strike together and strike fast in unexpected places.
Maginot Line: One of the then most heavily defended area, complete with trenches and pillboxes, that stretch from northern part of France (bordered with Germany) to the southern part. The Northern part was weaker, due to the miscalculation that the Germans could not bring their armored divisions through Ardenness forest.
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