Читать книгу Cryptocurrency All-in-One For Dummies онлайн

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The way that Bitcoin coordinates the organization and input of new data consists of three core elements:

 Block: A list of transactions recorded into a ledger over a given period. The size, period, and triggering event for blocks is different for every blockchain.Not all blockchains are recording and securing a record of the movement of their cryptocurrency as their primary objective. But all blockchains do record the movement of their cryptocurrency or token. Think of the transaction as simply being the recording of data. A value is assigned to it (as happens in a financial transaction) in order to interpret what that data means.

 Chain: A hash that links one block to another, mathematically “chaining” them together. This is one of the most difficult concepts in blockchain to comprehend. It’s also the magic that glues blockchains together and allows them to create mathematical trust.The hash in blockchain is created from the data that was in the previous block. The hash is a fingerprint of this data and locks blocks in order and time. Although blockchains are a relatively new innovation, hashing is not. Hashing was invented over 30 years ago. This old innovation is being used because it creates a one-way function that cannot be decrypted. A hashing function creates a mathematical algorithm that maps data of any size to a bit string of a fixed size. A bit string is usually 32 characters long, which then represents the data that was hashed. The Secure Hash Algorithm (SHA) is one of the cryptographic hash functions used in blockchains. SHA-256 is a common algorithm that generates an almost-unique, fixed-size 256-bit (32-byte) hash. For practical purposes, think of a hash as a digital fingerprint of data that is used to lock it in place within the blockchain.