Bitcoin is like cash, but simply digital. Because it is digital, peer-to-peer payments can now be made over long distances. Alice can send Bob 1,000 satoshis, where Alice is in Europe and Bob is in America. The special thing about this is that Alice can send the 1`000 Satoshis directly to Bob. There is no need for a third party to carry out the transaction, which you then have to trust.
So there is no point in having your satoshis in a bank, because you are giving up control of your satoshis, even though it is not even necessary.
Keep control of your satoshis and store them safely in a wallet. For small amounts, a software wallet on your smartphone, for example, is fine. However, it is best to use a hardware wallet.
There are now providers where you can buy satoshis and send them directly to your own wallet of choice. The purchase is made with a normal bank transfer.
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