“The Truth Machine” (La máquina de la verdad) is a general introduction in Spanish to the basic concepts underlying Blockchain and Bitcoin technologies. This basic book is among the first to be published in Spanish on the “Second Internet Revolution” concerning Blockchain. There are very few texts, and little information in the web, for Spanish speaking students, professionals and investors on Blockchain, the revolutionary distributed database technology supporting the bitcoin international digital currency invented by a mysterious, unidentified ‘Satoshi Nakamoto’. Bitcoin allows affordable direct peer-to-peer transfer of money and value without a trusted third party, and is arousing massive excitement and expectations around the world, along with a $20 billion market capitalization. The exchange rate of bitcoin to US dollars has increased more than 20,000-fold since its launching in 2009. The price of bitcoin has soared from a few cents to more than $1200 USD, and is driving a craze in some Spanish speaking countries plagued by a high inflation rate, monetary crisis and devaluation of official currency. This basic text covers the elementary core concepts, such as Distributed Ledger Technology, cryptography and crypto currencies, autonomous user-managed platforms, non monetary applications, international legislation, and other ideas and developments behind Blockchain, a decentralized and encrypted way of distributing, sharing, and storing information which is bound to become a disruptive technology that will change business practices and the economy in the years to come.