What is the Blockchain?
A blockchain, originally block chain, is a continuously growing list of records, called blocks, which are linked and secured using cryptography. Bitcoin is dependent on the blockchain that underlies and structures the system. The blockchain is the vertebrae of the protocol and the glue that holds the network together. It is simply a vast, distributed public ledger of account. It keeps track of every transaction ever made in the network, and all transactions are timestamped and verified by network miners. This is how it works: miners with specialized computers compete to solve mathematical puzzles with other computers, and once they solve a puzzle they are awarded with some Bitcoin, but they also add a “block” of completed transactions to the blockchain for future viewing and verifiability.
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