What were the immediate and long-term effects of using the atomic bomb?

The immediate effects are easy. Miles of city would be leveled and all inhabitants of that area would be almost instantly killed. The long-term effects would be there would be so much radiation your body could go through nasty mutation and you'd need to be treated if you survived but if don't survive you'd have a long agonizing death. Also all neighboring cities would have radiation surging through them.