$BTC One of the main features of the system is complete decentralization: there is no central administrator or any equivalent. The necessary and sufficient element of this payment system is the basic client program (it has open source code). The client programs running on multiple computers connect to each other in a peer-to-peer network, each node of which is equal and self-sufficient. One of the consequences of decentralization is the potential possibility of "double spending", that is, transferring the same bitcoins to different recipients. Under normal conditions, this is prevented by the inclusion of the transaction in the blockchain. However, if one controls more than 50% of the total computing power of the Bitcoin network, there is a theoretical possibility to "replace" one chain of transactions with another.

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