hinduism, buddhism and reincardnation

   Does anyone believe in reincardnation? Does it really exist? I have a theroy on this subjet, actually i have been thinking about this for a while. And it has to do with a fear i have, i wont go into details right now. I will have to do further research. But, as for my previous subjects, i do remember reading that hinduism and buddhism believe in reincardination. I will have to get back to you, about this topic; need to be more prepared.