The SAS is the UK's Special Air Service, an elite special forces regiment of the British Army.
The regiment is best known for counter-terrorism, reconnaissance, hostage rescue, and direct-action raids.
The SAS was formed during the Second World War and has since become associated with missions that need speed, surprise, and very small teams operating far behind enemy lines.
Here are some of the best-known missions by the SAS and how many soldiers are part of the SAS.
Iranian Embassy Siege
The Iranian Embassy Siege in London in 1980 is the SAS's most famous public counter-terrorist success.
Gambia Hostage Rescue
In 1981, the SAS carried out a hostage rescue in the Gambia.
Pebble Island Raid
The SAS conducted the Pebble Island raid during the Falklands War in 1982.
Operation Flavius
Operation Flavius was carried out in Gibraltar in 1988.
Operation Barras
In 2000, the SAS carried out Operation Barras in Sierra Leone.
Operation Trent
Operation Trent was carried out in Afghanistan in 2001.
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Basra Rescue
In 2005, the SAS carried out a rescue operation in Basra, Iraq.
These missions are just a snapshot of the SAS's work, as many of their operations are secret or only partially confirmed.
How many SAS soldiers do they have?
The SAS does not publish a simple exact headcount, but public sources describe it as a very small regiment made up of handpicked soldiers, supported by specialist reserve elements and enabling staff.
In practical terms, people usually mean the 22 SAS regular regiment, which is often described in the low hundreds, rather than a large conventional battalion-sized unit.
