A Bitcoin transaction is encrypted and digital.
The transaction is signed by the sending/outgoing wallet.
Then it is broadcast on the internet and listed on the Block Explorer log that keeps track of all bitcoin transactions.
This log is divided into blocks. Once a block is locked (in average every 10 minutes) the actual transaction takes place.
It is recommended to wait until there are at least 2-3 confirmations in order to ensure a bitcoin transaction.
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