A terrorist organization is a group that uses violence and intimidation, often against civilians, to achieve political, ideological, or religious goals. These groups may operate independently or as part of a larger movement and often seek to instill fear to influence governments or societies. Such organizations can vary widely in size, structure, and methods. Some are well-known, like Al-Qaeda or ISIS, while others may be smaller and less recognized. Governments and international bodies often work to combat these groups through law enforcement, military action, and diplomatic efforts.