Time bomb

A time bomb (or a timebomb, time-bomb) is a bomb whose detonation is triggered by a timer. The use (or attempted use) of time bombs has been for various purposes including insurance fraud, terrorism, assassination, sabotage and warfare. They are a popular feature in fictional thriller and action films as they offer a way of imparting a dramatic sense of urgency.

The explosive charge is the main component of any bomb, and makes up most of the size and weight of it. It is the damaging element of the bomb (along with any fragments or shrapnel the deflagration might produce with its container or neighboring objects). The explosive charge is detonated by a detonator.

A time bomb's timing mechanism may be professionally manufactured, either separately or as part of the device, or it may be improvised from an ordinary household timer such as a wind-up alarm clock, wrist watch, digital kitchen timer, or notebook computer. The timer can be programmed to count up or count down (usually the latter; as the bomb detonates when the time runs out).

Types of time bombs include:

Time bombs are common plot devices used in action/thriller TV series, cartoons, films and video games, where the hero often escapes the blast area or defuses the bomb at the last second. Many fictional time bombs are improvised, and usually involve a beeping sound with a large prominent countdown timer (on rare occasions, the timer will count up).

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