What is greek fire and what was it used for

It was a secret weapon used by the roman empire and it was used in battle to surprise the enemy with mass destruction.

Back then, they used to fight with wooden ships

it basically was able to be on fire while on the water

they could spray this stuff at the enemy and they could catch fire

so like liquid fire

so being able to spray fire at the enemy and the fire burns on the water while the enemy is fighting in wooden ships was a great tactic