Self-defense or defense of another is the use of physical force or violence against an aggressor in order to protect oneself or another person from harm. It is the legal right of an individual to defend themselves or another person from physical attack or harm. Self-defense or defense of another can be classified into two broad categories: physical self-defense and psychological self-defense. Physical self-defense is the use of physical force to protect oneself or another person from physical attack or harm. Examples of physical self-defense include blocking an attack, striking an assailant, using a weapon, or using restraints. Psychological self-defense is the use of psychological techniques to protect oneself from harm. Examples of psychological self-defense include distraction techniques, verbal de-escalation, and assertiveness. In legal terms, self-defense or defense of another is a valid legal defense for an individual accused of committing a crime. To prove self-defense, an individual must show that they had a reasonable belief that they were in imminent danger of death or serious bodily harm, or that another person was in imminent danger of death or serious bodily harm.