Changes

The first submarine commissioned into the United States Navy was the USS ''Holland''.  She was commissioned on Columbus Day in 1900 and was subsequently designated SS 1.   

The first submarine commissioned into the United States Navy was the USS ''Holland''.  She was commissioned on Columbus Day in 1900 and was subsequently designated SS 1.   

Submarines played a significant role in both World Wars I and II, and to this day many nations have submarine fleets, varying from the large, highly trained nuclear fleets of of the United States and the United Kingdom, to countries owning one Kilo class diesel submarine.

Submarines played a significant role in both World Wars I and II, and to this day many nations have submarine fleets, varying from the large, highly trained nuclear fleets of the United States and the United Kingdom, to countries owning one Kilo class diesel submarine.

   

   

Various different power sources have been used on submarines over the years.  The ''Hunley'' was powered by its crew turning a crank which was connected to the propeller.  Petrol engines have also been used, but they gave way to diesel engines.  Hydrogen peroxide was used in some German submarines during [[World War II]].  More recently nuclear power has been used.  It should be noted it this context that the term "nuclear submarine" refers to a submarine that uses nuclear power for propulsion, not necessarily one which carries nuclear weapons.

Various different power sources have been used on submarines over the years.  The ''Hunley'' was powered by its crew turning a crank which was connected to the propeller.  Petrol engines have also been used, but they gave way to diesel engines.  Hydrogen peroxide was used in some German submarines during [[World War II]].  More recently nuclear power has been used.  It should be noted it this context that the term "nuclear submarine" refers to a submarine that uses nuclear power for propulsion, not necessarily one which carries nuclear weapons.