Introduction to blockchain and cryptocurrencies

Abstract

The technology used by cryptocurrencies, such as blockchains, made it possible for users to transact with each other without needing a trusted third-party entity (a bank for example). Cryptocurrencies (like Bitcoin and Monero) can be defined as trustless decentralized systems which operate without a financial intermediary, making it possible to build decentralized payment systems where users are able to send payments securely without establishing trust. Due to those characteristics, the use of blockchains has spread rapidly among traditional financial systems. Large banks and corporations are investing heavily in the technology, aiming to increase its systems eficiency and reduce the costs of international transactions. Ripple was one of the first cryptocurrencies directed to financial institutions. The application of technologies brought by cryptocurrencies spread quickly to difierent areas with the intent of solving a myriad of problems. This tutorial presents an introduction to the technologies utilized by cryptocurrencies. The main objective is to share knowledge about the topic and promote the development of research involving those technologies. We discuss the fundamentals of blockchains and the cryptocurrencies Bitcoin and Monero, with emphasis on data security and privacy.