War occurred when two countries became jealous of each other and wanted their empires to grow. World War-I began in 1914 and lasted for 4 years. World War – II began in 1939 and lasted for 6 years after USA dropped atomic bomb over two Japanese cities – Hiroshima and Nagasaki. Millions of soldiers and other people were killed or wounded.
Nations of the world came together to find ways of preventing wars and United Nations was formed. British occupied India as she was very rich in pearls, diamonds, gold, spices and other raw materials for their factories. They colonized India. Indians fought against British for their independence.
War can happen any time in future. But United Nation steps in, to solve conflicts between nations, the same way as our parents who interfere to solve fights between our friends. I conclude by saying that we should try to prevent war and maintain peace in the world to prevent loss of life and mass destruction.