Cyberstalking involves threatening or unwanted behavior directed at someone using the internet and other online communication methods. It can include behaviors like unwanted emails, instant messages, identity theft, and tracing someone's online activity. Victims may experience psychological trauma like shock, disbelief, and changes in eating or sleeping patterns. People can help prevent cyberstalking by staying anonymous online, only using primary email for communication, filtering emails, reporting offenders, and telling trusted adults if under 18 and experiencing harassment.