A mercenary is a professional soldier who is hired to fight for a foreign country or organization, rather than serving in their own nation's military. They are often motivated by financial gain rather than loyalty to a specific cause or government. Mercenaries can be found in various conflicts around the world, providing military services such as combat, training, and security. The use of mercenaries raises ethical and legal questions, as their involvement can complicate international relations and accountability in warfare. Organizations like the United Nations have sought to regulate or limit the use of mercenaries to ensure that conflicts are managed by official state military forces.