Peacekeeping is the work of preventing or stopping violence between groups that are fighting, usually by sending neutral soldiers or observers to keep the sides apart. When two countries sign a peace agreement after a war, peacekeeping forces might patrol the border between them to make sure neither side breaks the truce. United Nations peacekeepers, wearing their distinctive blue helmets, have helped maintain ceasefires and protect civilians in dozens of conflicts around the world.

The job of peacekeepers isn't to fight battles or take sides. Instead, they act as referees, monitoring agreements and helping both sides follow the rules they agreed to. They might staff checkpoints, escort aid workers delivering food and medicine, or stand between two groups to discourage either from attacking.

The term can also describe smaller-scale efforts to prevent conflict. A teacher might take on a peacekeeping role when two students are arguing, or a parent might do peacekeeping work between siblings who won't stop bickering. In any case, peacekeeping means working to maintain calm and prevent disputes from turning into fights.