STS-1 was the first orbital spaceflight of NASA's Space Shuttle program. The first orbiter, Columbia, launched on April 12, 1981, and returned on April 14, 1981, 54.5 hours later, having orbited the Earth 37 times. Columbia carried a crew of two—mission commander John W. Young and pilot Robert L. Crippen. It was the first American crewed space flight since the Apollo–Soyuz Test Project (ASTP) in 1975. STS-1 was also the maiden test flight of a new American spacecraft to carry a crew, though it was preceded by atmospheric testing (ALT) of the orbiter and ground testing of the Space Shuttle system.

The Space Transportation System (STS), also known internally to NASA as the Integrated Program Plan (IPP), was a proposed system of reusable crewed space vehicles envisioned in 1969 to support extended operations beyond the Apollo program. The purpose of the system was two-fold: to reduce the cost of spaceflight by replacing the current method of launching capsules on expendable rockets with reusable spacecraft; and to support ambitious follow-on programs including permanent orbiting space stations around Earth and the Moon, and a human landing mission to Mars.