A paramilitary is a force whose function and organization are similar to those of a professional military, but which is not considered part of a state's formal armed forces.
The term paramilitary is subjective, depending on what is considered similar to a military force, and what status a force is considered to have. The nature of paramilitary forces therefore varies greatly according to the speaker and the context.
For instance, in Northern Ireland, paramilitary refers to any illegal armed group with a political purpose, but in Colombia, paramilitary refers only to illegal armed right-wing groups (such as the United Self-Defense Forces of Colombia) that are not in direct opposition to the government, while illegal armed left-wing groups rebelling against the government (such as Revolutionary Armed Forces of Colombia) are referred to as guerrillas.
Depending on context, paramilitaries can include:
Gendarmeries, e.g. Egyptian Central Security Forces and India's Central Reserve Police Force . Security forces of ambiguous military status, e.g. Russia's Internal Troops
Border guards, e.g. India's Border Security Force
Fire Departments and Fire Brigades.
Insurgent militia, irregular military, armed resistance movements and guerrilla forces which consider themselves military but which governments may consider terrorist, for example Provisional IRA, Ulster Volunteer Force, or United Self-Defense Forces of Colombia (AUC).
Armed units of US national intelligence services units such as the Special Activities Division of the Central Intelligence Agency (CIA), or the Hostage Rescue Team of the Federal Bureau of Investigation (FBI).
Auxiliary services of armed forces.
Youth cadet organizations with no wartime role, e.g. India's National Cadet Corps
The Schutzstaffel (SS) and Sturmabteilung (SA) in Nazi Germany