Bitcoin is the first and most well-known, but there are thousands of types of cryptocurrencies. Many, like Litecoin and Bitcoin Cash, share Bitcoin’s core characteristics but explore new ways to process transactions. Others offer a wider range of features. Ethereum, for example, can be used to run applications and create contracts. All four, however, are based on an idea called the blockchain, which is key to understanding how cryptocurrency works.

• At its most basic, a blockchain is a list of transactions that anyone can view and verify. The Bitcoin blockchain, for example, is a record of every time someone sends or receives bitcoin. This list of transactions is fundamental for most cryptocurrencies because it enables secure payments to be made between people who don’t know each other without having to go through a third-party verifier like a bank.

• Blockchain technology is also exciting because it has many uses beyond cryptocurrency. Blockchains are being used to explore medical research, improve the sharing of healthcare records, streamline supply chains, increase privacy on the internet, and so much more.

• The principles behind both bitcoin and the Bitcoin blockchain first appeared online in a white-paper published in late 2007 by a person or group going by the name Satoshi Nakamoto.

• The blockchain ledger is split across all the computers on the network, which are constantly verifying that the blockchain is accurate.This means there is no central vault, entity, or database that can be hacked, stolen, or manipulated.