Nuclear weapons are meant to destroy and injure masses. It generates this destructive force from either of nuclear reactions fusion or fission. When compared with other weapons of mass destruction, nuclear weapons have greater destructive power even though it uses a very small quantity of the nuclear compound. Unlike other weapons which can destroy two or three blocks at their best, nuclear weapons can destroy the entire city in one go.
If we go in the history of wars that were fought between two countries we see that these weapons have been put to use only twice. Both these times USA was the culprit and Japan was the sufferer. First bomb was dropped on Hiroshima on 6th of august 1945. It was a uranium gun type bomb and was named “Little Boy”. Second bomb was dropped on Nagasaki on 9th of august 1945. It was a plutonium implosion type bomb and was named as ‘fat man’. Both these bombs took life of more than two hundred thousand people immediately and far more over the period of time.
However these bombs haven’t been used in active war since then but many countries have detonates them for the sake of demonstration. There are many countries which posses this power at the moment and only God knows what will happen if these countries indulge themselves in a war and blow these bombs off.