Bitcoin is a digital currency that is decentralized and based on a technology called blockchain. It was introduced in 2009 by an unknown person or group of people under the pseudonym Satoshi Nakamoto. Bitcoin allows users to conduct transactions without the need for a central authority, such as a bank. Transactions are recorded on a public ledger, the blockchain, which is shared by many computers around the world. Bitcoin can be used to purchase goods and services, as well as invest and trade on various exchanges. There is a limited amount of Bitcoin that can ever be created, which sets it apart from traditional currencies that can be printed by governments. Bitcoin is often viewed as digital gold or an alternative asset class.