Bitcoin is digital money used for secure and instant transfer of value anywhere in the world. It is not controlled or issued by any bank or government - instead it is an open network which is managed by its users. Much in the way email improved communication by making it fast and cheap, bitcoin is an improvement on existing payment methods which were not designed for the internet era.
Bitcoin was invented in 2008 as a peer-to-peer payment system for use in online transactions. Unlike any prior payment system, bitcoin is revolutionary in that it is not controlled by any government. This designation allows for the achievement of possibilities that have been previously unattainable in the world of finance. Namely, due to the fact that no central authority is responsible for bitcoin, it cannot be debased, controlled or otherwise used as a political tool. Since bitcoin is also a peer-to-peer network, there is no need for a third party or "middleman" to facilitate transactions between a buyer and seller.
Instead of a central authority, the bitcoin transaction network consists of computers around the world running the bitcoin software, which operates the protocol for administering bitcoin transactions. That software can be downloaded and run by anyone, and any computer running the software can join the network. Each computer on the network also maintains a copy of the universal public ledger known as the "block chain".
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