So, I had this question in my mind for a little time and now I think I really need an answer.
If you create a btc address you get the private key of that address, what if this address is already in use ?
I know there is a really low probability but this can happen, am I right ?
Millions of people have their own private key and it is extremely impossible for a stranger to know that you are that person he shares the same private key with. Similar private keys could happen because combinations of characters are finite. But do not let this bug your mind because this is a one in a million chance to occur.