Bitcoin Billionaire Reviews : In early 2009, Nakamoto released Bitcoin to the public, and a group of enthusiastic supporters began exchanging and mining the currency. By late 2010, the first of what would eventually be dozens of similar cryptocurrencies – including popular alternatives like Litecoin – began appearing. The first public Bitcoin exchanges appeared around this time as well. Cryptocurrency users have “wallets” with unique information that confirms them as the temporary owners of their units. Whereas private keys confirm the authenticity of a cryptocurrency transaction, wallets lessen the risk of theft for units that aren’t being used.