What is the difference between attack and supply hose lines?

Attack hose lines are designed for delivering water directly to the fire, typically being smaller in diameter and used for offensive firefighting operations. They are often deployed in high-pressure situations to quickly suppress flames. In contrast, supply hose lines are larger and intended to transport water from the source, such as a hydrant, to the fire scene or to a pump, providing the necessary water pressure for attack lines. Essentially, attack lines are for direct firefighting, while supply lines are for water delivery.