Bitcoin is known as a type of cryptocurrency because it uses cryptography to keep it secure. There are no physical bitcoins, only balances kept on a public ledger that everyone has transparent access to (although each record is encrypted).
Read moreIs Bitcoin actually a coin?
In truth there is no such thing as a bitcoin or a wallet , just agreement among the network about ownership of a coin. A private key is used to prove ownership of funds to the network when making a transaction.
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