An armoured spearhead (American English: armored spearhead) is a formation of armoured fighting vehicles, mostly tanks, that form the front of an offensive thrust during a battle. The idea is to concentrate as much firepower into a small front as possible, so any defenders in front of them will be overwhelmed. As the spearhead moves forward, infantry units following in the gap behind them form up on either side of the line of advance in order to protect the flanks.