Bullying no longer occurs solely in schools or workplaces, but also on the internet today. Applications such as social communities, video platforms, or blogs are increasingly used to harass, embarrass, or threaten others. The term cyberbullying has been coined for this form of bullying. What changes occur in comparison to traditional bullying? Does the nature of bullying change? What causes can be identified, and what effects does cyberbullying have on the victims? This qualitative study investigates these questions. The empirical basis consists of 16 expert interviews as well as four guided interviews with victims of cyberbullying. The work provides fundamental insights and thus offers a good overview of this form of bullying.