Mining is a record-keeping service done through the use of computer processing power.[e] Miners keep the blockchain consistent, complete, and unalterable by repeatedly grouping newly broadcast transactions into a block, which is then broadcast to the network and verified by recipient nodes. Each block contains a SHA-256 cryptographic hash of the previous block, thus linking it to the previous block and giving the blockchain its name.:ch. 7
Bitcoin is a digital currency that enables users to be their own banks, store their assets securely thanks to advanced encryption and send money without any intermediaries to anyone anywhere in the World. Bitcoin is the oldest cryptocurrency with a very good market price. It has made many investors, especially the earliest ones, incredibly rich bringing even 1000x of returns. However, because of this it has become a very speculative asset. Many people are researching Bitcoin only for the sake of profits and not to use it as a fast peer-to-peer payment method
In early February 2014, one of the largest bitcoin exchanges, Mt. Gox, suspended withdrawals citing technical issues. By the end of the month, Mt. Gox had filed for bankruptcy protection in Japan amid reports that 744,000 bitcoins had been stolen. Months before the filing, the popularity of Mt. Gox had waned as users experienced difficulties withdrawing funds.