 After the heyday of totalitarian terrorism in the 1930s and 1940s, internal state terrorism continued to be practiced by military dictatorships in many parts of the world, albeit in a less sustained and pervasive way. But the type of terrorism that came to the fore in the second half of the 20th century and in early 21st century is that employed by insurgent organizations. Many movements for national liberation from colonial rule resorted to it, either as the main method of struggle or as a tactic complementing guerrilla warfare. So did some separatist movements. Some organizations driven by extreme ideologies, in particular on the left, took to terrorism as the way of trying to destroy what they considered an unjust, oppressive economic, social and political system. This type of terrorism is, by and large, indiscriminate in its choice of target: it attacks men and women of whatever political (or apolitical) views, social class, and walk of life; young and old, adults and children. It shoots at people, or blows them up by planting bombs, in office buildings, markets, cafes, cinemas, places of religious worship, on buses or planes, or in other vulnerable public places. It also takes people hostage, by hijacking planes and in other ways.