This paper will introduce us to the so-called "cryptocurrencies", or "digital currencies". Perhaps they will not be, as their advocates propose, "as big as the printing press", but their development bequeathed a great tool: blockchains as public data structures (or shared to all members of a network) applicable to old and new legal and civic operations. Among them, "Bitcoin" stands out for now, which is an electronic currency, a protocol and a software, inspired by the crypto-anarchist manifesto written by Timothy C. May in 1992, in which he proposed the creation of a crypto-currency. May in 1992, in which he proposed the creation of a network of users that eliminates all types of state or private intermediation. May claimed that the impact of the creation of such a network, safeguarded by the use of encryption, would weaken the power of financial institutions just as the printing press weakened the power of medieval guilds. His prophecy came true, although it remains to be seen whether it will have an impact similar to that of the printing press, Bitcoin brought the ideas of the crypto-anarch manifesto to reality and turned them into a real system through blockchain technology.