<P> There is no universal definition of bullying, however, it is widely agreed upon that bullying is a subcategory of aggressive behavior characterized by the following three minimum criteria: (1) hostile intent, (2) imbalance of power, and (3) repetition over a period of time . Bullying may thus be defined as the activity of repeated, aggressive behavior intended to hurt another individual, physically, mentally or emotionally . </P> <P> The Norwegian researcher Dan Olweus says bullying occurs when a person is "exposed, repeatedly and over time, to negative actions on the part of one or more other persons". He says negative actions occur "when a person intentionally inflicts injury or discomfort upon another person, through physical contact, through words or in other ways ." Individual bullying is usually characterized by a person behaving in a certain way to gain power over another person . </P> <P> Individual bullying can be classified into four types . Collective bullying is known as mobbing, and can include any of the individual types of bullying . </P> <P> Physical, verbal, and relational bullying are most prevalent in primary school and could also begin much earlier whilst continuing into later stages in individuals lives . It is stated that Cyber-bullying is more common in secondary school than in primary school . </P>

Name one of the many methods that bullying can be carried out through