Here is death: No heartbeat. No brain activity. Not moving. Not Breathing. Therefore, you are dead.
As for what happens after death, of course, that is the great mystery of time. Nobody knows and nobody will ever know. Not even the highest science could tell you what happens. I suppose science would say you cease to exist, therefore, you are just gone. I don't know. I'd say there is a heaven.
I dont think that we understand the concept of death. Sure we all have our moments but lets be honest, what we see in movies and read in books isnt true until you see for yourself. Many people say death is heaven, some say death is satans child. But lets face some reality here, who knows what death is truly like? Have you died? Have u had a talk with death? No so i dont think anyone truly understands death. Like what if death meant that when its your time to go you wake up in a child and the life u lived and died for was all just a big dream and it countines? Then what? So no. Death can be seen in many angles but it just takes the right path to help you understand death.