Soyuz (Russian: Союз, meaning "union", GRAU index 11A511) is a family of Soviet expendable launch systems developed by OKB-1 and manufactured by Progress Rocket Space Centre in Samara, Russia. With over 1700 flights since its debut in 1966, the Soyuz is the most frequently used launch vehicle in the world.[1]
For nearly a decade between the final flight of the U.S. Space Shuttle program in 2011 and the 2020 first crewed mission on SpaceX's Falcon 9 rocket, Soyuz rockets were the only launch vehicles able and approved to transport astronauts to the International Space Station.
The Soyuz vehicles are used as the launcher for the crewed Soyuz spacecraft as part of the Soyuz program, as well as to launch uncrewed Progress supply spacecraft to the International Space Station and for commercial launches marketed and operated by Starsem and Arianespace. All Soyuz rockets use RP-1 and liquid oxygen (LOX) propellant, with the exception of the Soyuz-U2, which used Syntin, a variant of RP-1, with LOX. The Soyuz family is a subset of the R-7 family.