During the last several years an incredible amount of Bitcoin mining power (hashrate) has come online making it harder for individuals to have enough hashrate to single-handedly solve a block and earn the payout reward. To compensate for this pool mining was introduced. Pooled mining is a mining approach where groups of individual miners contribute to the generation of a block, and then split the block reward according the contributed processing power.
The use of bitcoin by criminals has attracted the attention of financial regulators, legislative bodies, law enforcement, and the media. In the United States, the FBI prepared an intelligence assessment, the SEC issued a pointed warning about investment schemes using virtual currencies, and the U.S. Senate held a hearing on virtual currencies in November 2013. The U.S. government claimed that bitcoin was used to facilitate payments related to Russian interference in the 2016 United States elections.
The domain name "bitcoin.org" was registered on 18 August 2008. In November 2008, a link to a paper authored by Satoshi Nakamoto titled Bitcoin: A Peer-to-Peer Electronic Cash System was posted to a cryptography mailing list. Nakamoto implemented the bitcoin software as open source code and released it in January 2009. Nakamoto's identity remains unknown.