From suicide bombers and executioners to weapons experts and religious police, the ISIS uses a complex network of militants to wage its terror war in the Middle East.
To differentiate the various roles within its hierarchy, it has, perhaps more than other military organization, sought to assign corresponding uniforms for each unit.
These, say anti-ISIS activists who live in the shadows in the terror group's de facto capital Raqqa in Syria, can be broken down into several categories, each as sinister as the next.
According to activists “Raqqa Is Being Slaughtered Silently” (RIBSS), it is also worn by the 'princes of ISIS' – or senior figures – in battle and for those conducting reconnaissance missions.
A sandy-colored desert camouflage version, meanwhile, is assigned to the terrifying special units responsible for the group's barbaric executions.
Other senior executioners, however, like the British extremist known as “Jihadi John”, also to wear head-to-toe black robes.
A similar all-black outfit, with a black sweater and usually without the ammunition belt, is worn by fanatics during parades, as seen when they captured the Syrian city of Raqqa last year and several other town and villages since.
A further variation is given to militants responsible for training the next generation of recruits at its terror camps, consisting of a pair of black trousers with a long beige jacket.