Читать книгу Cryptocurrency All-in-One For Dummies онлайн

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A ledger is the age-old record-keeping system for recording information and data. Cryptocurrencies use a public ledger to record all transactional data. Everyone in the world can access public blockchains and see entire transactions happening with cryptocurrencies.

Note that not all blockchains use a public ledger. Some businesses and financial institutions use private ledgers so that the transactions aren’t visible to the world. However, by doing so, they may contradict the original idea behind blockchain technology.

Smart contracts are also called self-executing contracts, blockchain contracts, or digital contracts. They’re just like traditional contracts except that they’re completely digital. Smart contracts remove the middleman between the buyer and the seller so that you can implement features like automatic payments and investment products without the need for a central authority like a bank.

A smart contract is actually a tiny computer program that’s stored and runs on a blockchain platform. Because of that, all the transactions are completely distributed, and no centralized authority is in control of the money. Also, because it’s stored on a blockchain, a smart contract is immutable. Being immutable means that after a smart contract is created, it can never be changed again; it can’t be tampered with, which is an inherited feature from blockchain technology.