A violent crime, violent felony, crime of violence or crime of a violent nature is a crime in which an offender or perpetrator uses or threatens to use harmful force upon a victim. This entails both crimes in which the violent act is the objective, such as murder, assault, rape and assassination, as well as crimes in which violence is used as a method of coercion or show of force, such as robbery, extortion and terrorism. Violent crimes may, or may not, be committed with weapons. Depending on the jurisdiction, violent crimes may be regarded with varying severities from homicide to harassment. There have been many theories regarding heat being the cause of an increase in violent crime. Theorists claim that violent crime is persistent during the summer due to the heat, further causing people to become aggressive and commit more violent crime.