Terrorism has arguably been one of the defining factors of our age. It frequently makes headlines, threatening or attacking governments, private business and ordinary citizens. And in many parts of the world, it has been one of the most important threats to peace, security and stability. But what does this exactly mean? What is the nature of this threat? Who or what is threatened, how, by whom and why? What can be done about it or how can we at least limit the impact of terrorism and make sure that terrorists do not make headlines and manage to scare us?