Aggression, in its broadest sense, is behavior, or a disposition, that is forceful, hostile or attacking. It may occur either in retaliation or without provocation. In narrower definitions that are used in social sciences and behavioral sciences, aggression is an intention to cause harm or an act intended to increase relative social dominance. Predatory or defensive behavior between members of different species may not be considered aggression in the same sense. Aggression can take a variety of forms and can be physical or be communicated verbally or non-verbally.
Aggression differs from what is commonly called assertiveness, although the terms are often used interchangeably among laypeople, e. g. an aggressive salesperson According to Kendra Cherry, In psychology, the term ‘aggression’ refers to a range of behaviors that can result in both physical and psychological harm to oneself, other or objects in the environment. The expression of aggression can occur in a number of ways, including verbally, mentally and physically. (source: aboutpsychology. om) Two broad categories of aggression are commonly distinguished.
One includes affective (emotional) and hostile or retaliatory aggression, and the other includes instrumental, goal-oriented or predatory aggression.  Data on violence from a range of disciplines lend some support to a distinction between affective and predatory aggression.  However, some researchers question the usefulness of a hostile vs instrumental distinction in humans, despite its ubiquity in research, because most real-life cases involve mixed motives and interacting causes. 4] A number of classifications and dimensions of aggression have been suggested.
These depend on such things as whether the aggression is verbal or physical; whether or not it involves relational aggression such as covert bullying and social manipulation; whether harm to others is intended or not; whether it is carried out actively or expressed passively; and whether the aggression is aimed directly or indirectly. Classification may also encompass aggression-related emotions (e. g. anger) and mental states (e. g. impulsivity, hostility). 6] Aggression may occur in response to non-social as well as social factors, and can have a close relationship with stress coping style. 7]
Aggression may be displayed in order to intimidate. The operative definition of aggression may be affected by moral or political views. Examples are the axiomatic moral view called the non-aggression principle and the political rules governing the behavior of one country toward another.  Likewise in competitive sports, or in the workplace, some forms of aggression may be sanctioned and others not.  THEORIES OF AGGRESSION: Instinct Theory: Through evolution, humans have inherited a fighting instinct similar to that found in many species of animals.
Leading Proponent: Konrad Lorenz (ethology) He says we have a biological need for aggression. It gets stronger as time passes since the last aggressive act (like hunger increases hours after a meal). This causes our energy level (drive level) to increase. This energy must somehow be released (“catharsis”). Instinct Theory says that humans learn their own individual ways of expressing aggressive motivation. Nonhuman species behave in ways that are genetically programmed and characteristic of all members of the species.
Fixed Action Pattern: complex behavior that is largely unlearned and found in all members of a species (or subgroup), and that is triggered by a very simple stimulus in the environment (“releaser”). Social Learning Theory: Human aggression is largely learned by watching other people behave aggressively, either in person or in films. It is also learned when we are rewarded for aggression. Leading Proponent: Albert Bandura Frustration-Aggression Hypothesis: Our motivation for aggression increases when our ongoing behavior is interrupted or we are prevented from reaching a goal.
Negative Affect Theory: Proposed by Leonard Berkowitz, it states that negative feelings and experiences are the main cause of anger and angry aggression. Sources of anger include: pain, frustration, loud noise, foul odors, crowding, sadness, and depression. The likelihood that an angry person will act aggressively depends on his or her interpretation of the motives of the people involved. TYPES OF HUMAN AGGRESSIVE BEHAVIOUR: PHYSICAL VIOLENCE- Physical aggression often involves acts of violence taken with the intention of causing harm to the recipient, including death, by using weapons or even someone’s bare hands. VERBAL HOSTILITY- Verbal aggression includes behavior such as bullying, threats or yelling.
The Mayo Clinic includes name-calling and insults under the category of domestic violence. Put-downs, intentional or perceived, can have profound detrimental effects on the recipients. * NON-VERBAL INTIMIDATION- Nonverbal intimidation often implies the threat of violence, at least in the perception of the person at the receiving end.
Stalking often involves one or more forms of nonverbal intimidation, including following the victim, planting malicious software in a victim’s computer, sending unwanted gifts and vandalism against the victim’s property. * PASSIVE AGGRESSION- Passive aggression is often generated by resentment on the part of someone who is unable or unwilling to express this resentment directly. PURPOSE OF AGGRESSION: Aggression can also serve a number of different purposes: To express anger or hostility To assert dominance To intimidate or threaten To achieve a goal To express possession
A response to fear A reaction to pain To compete with others Researchers have suggested that individual who engage in affective aggression, defined as aggression that is unplanned and uncontrolled, tend to have lower IQs than people who display predatory aggression. Predatory aggression is defined as aggression that is controlled, planned and goal-oriented. AGGRESSION AND MEDIA: Scholars believe that behaviors like aggression may be partially learned by watching and imitating the behavior of others. Some scholars have concluded that media may have some small effects on aggression.
There is also research questioning this view. For instance, a recent long-term outcome study of youth found no long-term relationship between playing violent video games and youth violence or bullying. One study suggested there is a smaller effect of violent video games on aggression than has been found with television violence on aggression. This effect is positively associated with type of game violence and negatively associated to time spent playing the games. The author concluded that insufficient evidence exists to link video game violence with aggression.