Does defragmenting in Windows.....

kill your datas? or crush your PC? I do defragment sometimes but I'm so scared each time I do it. So please tell me the answer. Because my external hard drive is being quite slower then usual nowadays, I think I have to defragment the ex hard drive. Or is there anyother solution??

If your data is very dynamic and gets too fragmented too often, you'll stress your drive less by defragmenting often.