Answer:
NATO which stands for North Athlantic treat organisation was a group of allliance formed by the west nations such as USA, Canada, Britain, France and so on. In morden day this alliance could be compared to the European Union. NATO gave all the member states reassuarance that if any nation attacked any of the member states all the states will intervene. It was formed during the cold war with the USA being the main leader of this group.
Warsaw pact was formed on reaction to Nato. It was made up of Eastern Europe countries with USSR being the leader. Basically it was an alliance of eastern Europe countries. It was named Warsaw after the capital city of Poland because that's where the pact was formed.