$BTC
Unlike services like Venmo and PayPal, which rely on the traditional financial system for permission to transfer money and on existing debit/credit accounts, bitcoin is decentralized: any two people, anywhere in the world, can send bitcoin to each other without the involvement of a bank, government, or other institution.
Every transaction involving Bitcoin is tracked on the blockchain, which is similar to a bank’s ledger, or log of customers’ funds going in and out of the bank. In simple terms, it’s a record of every transaction ever made using bitcoin.