An injunction is a legal order that requires someone to do or refrain from doing something. It can be issued by a court and is usually sought by an individual or organization who believes they are being harmed in some way, such as through trespassing, defamation, or breach of contract. An injunction can also prevent someone from continuing certain behavior that is causing harm to others. In short, it's a tool used by the legal system to protect individuals and their rights.