Bitcoin is simply a mobile app or computer program that provides a personal Bitcoin wallet, allowing a user to send and receive bitcoins. This is how Bitcoin works for most users. But on the backend, the Bitcoin network records what is essentially a public ledger called the “block chain”. This ledger contains every transaction ever processed, allowing a user’s computer to verify the validity of each transaction. The authenticity of each transaction is protected by digital signatures corresponding to the sending addresses, allowing all users full control over sending and receiving bitcoins from their own unique Bitcoin addresses – much like an email address. Additionally, anyone can process transactions using the computing power of specialized hardware to earn bitcoins in return. This is called “bitcoin mining”.