An accident is an unfortunate event that results in some kind of loss or damage. Accidents can happen in all circumstances and may range from trivial to catastrophic. Automobile accidents kill thousands of people annually, while the Chernobyl disaster resulted in the deaths of 10,000 to 50,000 people.

The victims of accidents are often protected by insurance. The insurance industry makes billions of dollars by using people's fear of loss or destruction of themselves/their property to sell financial products, creating statistical models of accident likelihoods. This is encompassed by the study of risk management.