U.S. Navy Damage Controlman 3rd Class Kenneth Bottorff, (left), receives his annual influenza immunization shot from Hospital Corpsman 3rd Class Christin Cashwell aboard the Nimitz Class Aircraft Carrier USS RONALD REAGAN (CVN 76) on Oct. 17, 2006. The REAGAN is currently conducting training squadron carrier qualifications off the coast of Southern California. (U.S. Navy photo by Mass Communication SPECIALIST SEAMAN Kathleen Gorby) (Released)

Aircraft carriers are warships that act as airbases for carrier-based aircraft. In the United States Navy, these consist of ships commissioned with hull classification symbols CV (aircraft carrier), CVA (attack aircraft carrier), CVB (large aircraft carrier), CVL (light aircraft carrier), CVN (aircraft carrier (nuclear propulsion) and CVAN (attack aircraft carrier (nuclear propulsion). The first aircraft carrier commissioned into the United States Navy was USS Langley (CV-1) on 20 March 1922.