Simplify the following text for a Grade 9 native English-speaking person.
Original: The battle has been called `` Typhoon of Steel '' in English , and `` tetsu no ame , '' `` tetsu no bÅ fÅ `` '' by the people of Okinawa , which mean `` rain of steel '' and `` violent wind of steel '' , because of the very heavy firing of guns and bombs at this battle .
Simplified: The battle has been referred to as the `` Typhoon of Steel '' in English , and tetsu no ame ( `` rain of steel '' ) or tetsu no bÅ fÅ `` ( `` violent wind of steel '' ) in Japanese .