Pyromania is an intense obsession with fire, explosives, and their related effects. It is also an obsession with starting fires in an intentional fashion. An individual with pyromania is referred to as a pyromaniac or "pyro" for short. In colloquial English, the synonyms "firebug" and "firestarter" are sometimes used. Pyromaniacs are identified specifically as not having any other symptoms but obsession with fire causing their behavior. It is distinct from arson, and pyromaniacs are also distinct from those who start fires because of psychoses, for personal, monetary or political gain, or for acts of revenge. Pyromaniacs start fires to induce euphoria, and often tend to fixate on institutions of fire control: fire stations, firefighters, etc.

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http://en.wikipedia.org/wiki/Pyromania