*SAS, SBS, SRR and others...
The Special Air Service, better known by its initials: SAS is a special forces regiment of the British Army (UKSF). Its functions are wartime special operations, and in peacetime, mainly counterterrorism.
Together with the Special Boat Service (SBS), Special Reconnaissance Regiment (SRR) and, from 2006, the Special Forces Support Group (SFSG) integrate the special forces of the British Army (UKSF). The regiment has served as a model for the creation of the special forces of many countries.
Although SAS has its origins in World War II, he was unveiled outside the military institution as one of the most respected elite units in the world after the successful Iranian Embassy Siege of 1980, when they raided at gunpoint the Iranian Embassy in London to rescue the hostages.