There is no consensus on the amount of media exposure of a person although it appears to be great in Western cultures. Violence is often defined as the overt expression of physical force. More than 60% of television programmes contain violence. However, it is not clear how violence is represented in television programmes, as the context, emphasis and frequency can differ. Exposure to violent media increases the incidence of aggressive behaviour, although there is less evidence for an increase in criminal violence. However, this evidence comes from experimental settings and it is difficult to generalize this type of aggression to real-life. Cross-sectional surveys demonstrate that exposure to violent television and movies are related to aggression. The relation between exposure to media violence and real-life aggression cannot be explained by aggressive individuals seeking out violent programmes. Meta-analyses demonstrate that exposure to violent media increases the level of aggressive and anti-social behaviour. There are several factors that may strengthen or weaken the impact of media violence:ConsequencesThe consequences of violence portrayed in the media may be an important factor, as violence that emphasizes the pain of the victim is difficult to ignore. Realism and contextThe more realistic violence is, the more likely it is to be imitated or copied. This includes whether violence in the media is justified or not, as justified violence promotes aggressive responses. Characteristics of the viewerThe characteristics of the viewer influence the effect violent media has on the individual. Young children are more easily influenced by violent media due to their inability to distinguish between realism and fantasy and people who are more aggressive are more likely to be influenced by violent media.There are several theories of media violence:Social learning theoryThis theory states that aggression can be learned through direct (e....