Bitcoin works by recording every transaction that takes place on its network in all nodes of the network. This redundancy ensures that a bad actor cannot change or delete a transaction by undermining a single point of failure.

Each user of the Bitcoin system has a public-private encrypted key pair, and use their public keys as their account number or address. For instance, if Alice sends Bob one Bitcoin, she will send it to Bob’s public key address. Transactions themselves are validated and added to the blockchain ledger through a process called “mining,” which also is the method by which new Bitcoins are introduced to the system.