Bullying is defined as repeatedly causing someone to feel stressed, humiliated or threatened in an effort to assert power or control over that person. The document discusses different types of bullying and provides scenarios to determine if they are examples of bullying or just conflicts. It emphasizes that bystanders have the power to stop bullying by defending victims, getting help from trusted adults, or reporting bullying anonymously through various methods. The most important thing is for students to avoid being targeted by staying with groups and building friendship skills.