The United States Navy's Sea, Air, and Land Teams, commonly known as Navy SEALs, are the U.S. Navy's principal special operations force and a part of the Naval Special Warfare Command (NSWC) and SOCOM.

"SEAL" is always capitalized in reference to members of the Naval Special Warfare community. The acronym is derived from their capacity to operate at sea, in the air, and on land. In the War on Terror, SEALs have been utilized almost exclusively for land-based operations, including Direct Action, Hostage Rescue, Counter Terrorism, Special Reconnaissance, unconventional warfare and foreign internal defense operations. Without exception, all SEALs are male members of the United States Navy. An exchange program with the Coast Guard, which graduated three Coast Guardsmen as SEALs, was suspended in 2011.

The CIA's highly secretive Special Activities Division (SAD) and more specifically its elite Special Operations Group (SOG) recruits operators from the SEAL Teams. Joint Navy SEALs and CIA operations go back to the famed MACV-SOG during the Vietnam War. This cooperation still exists today and is seen in the wars in Iraq and Afghanistan, and in the finding and killing of Osama bin Laden in Pakistan.

The United States Navy (USN) is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. It is the largest navy in the world, with a battle fleet tonnage that is greater than that of the next 13 largest navies combined. The U.S. Navy also has the world's largest carrier fleet, with 11 in service, one under construction (two planned), and one in reserve. The service had 328,516 personnel on active duty and 101,689 in the Navy Reserve in January 2011. It operates 283 ships in active service and more than 3,700 aircraft.

The Navy traces its origins to the Continental Navy, which was established during the American Revolutionary War and was essentially disbanded as a separate entity shortly thereafter. The United States Constitution provided the legal basis for a military force by giving Congress the power "to provide and maintain a navy".

Depredations against U.S. shipping by Barbary Coast pirates in the Mediterranean Sea spurred Congress to employ this power by passing the Naval Act of 1794 ordering the construction and manning of six frigates. These ships were used to end most pirate activity off the Barbary Coast. In the 20th century, American blue-water navy capability was demonstrated by the 1907–1909 world tour of the Great White Fleet.

Marcus Luttrell (born November 7, 1975) is a former Petty Officer First Class and United States Navy SEAL. He received the Navy Cross for his actions in 2005 facing Taliban fighters during Operation Red Wings.

He began training for the SEALs at age 15 with former United States Army soldier Billy Shelton, who lived near Luttrell's home. He trained every day with his twin brother, Morgan, and others who aspired to join the military. Shelton trained them using various weight and endurance exercises. After high school, Luttrell attended Sam Houston State University, where he joined the Delta Tau Delta fraternity.

Luttrell joined the United States Navy in March 1999. He began Basic Underwater Demolition/SEAL (BUD/S) training with Class 226 in Coronado, California. He graduated with Class 228 after suffering a fractured femur early in his training. He was deployed to Afghanistan in 2005 with SEAL Team Ten. Prior to Afghanistan, Luttrell had been part of SDV-1. After Operation Red Wings he transferred to SEAL Team Five and deployed to Operation Iraqi Freedom doing various operations there.