To own a coin, you need a private and public address of that coin. Although you have an account, if the website goes down then you are out of luck. To own a coin, you would want to store it in a wallet where if anything happened, you would have access it.

See the links I listed for the wallet setups. That is what I'm talking about. You can also buy hardware wallets (like Trezors and keepkeys, but those cost money)