Describe the roles of nato and the warsaw pact. why did they need to exist?

Hi, I know it's late but it is:

NATO and Warsaw Pact were a military organization at the time of the Cold War, adn they both had the objective of assuring mutual military protection from the other organization (or the particular countries from the other organization). So each of the countries in NATO/Warsaw Pack felt safer that if they're attacked by the other camp, all the other camps in their organization would come to help.

People felt that such organizations were needed, because of the deep mistrust that existed between the two, which was caused by the fact that both did not appreciate that the other tried to get new countries in their sphere of influence. So particuluarly, Soviet Union did not appreciate West Germany being included in the Western World (and NATO) and this event led to the creation of the Warsaw Pact.

There was never a direct confrontation between the two, but they led proxy wars, such as in Vietnam or Korea.