I just want to know how those people behind bitcoin secure the money they will invest because as far as I know there are lots of hackers all over the world.
Bitcoin itself is secure, the only one you should protect is your wallet and email, but you can't completely protect your wallet, you can put more security in your wallet like never share your private key and don't forget protect your email who connected to your wallets, i suggest you to use offline wallet because it better than online wallet.