Designed by an anonymous creator, Bitcoin is an intriguing and revolutionary modern technology and payment transaction infrastructure. But as with any new technology, there are many obstacles and threats on the path towards mainstream acceptance. What are the shortcomings of the Bitcoin protocol and Bitcoin as a currency? Moreover, which competitors may one day be able to surpass Bitcoin and make it obsolete? Could a suitable competitor replace Bitcoin, or will the open source virtual currency keep improving itself to make competition obsolete? Traditional classifications for currencies do not adequately apply to Bitcoin. It is a new type of financial technology that entered the global market in 2008 and has since been able to draw the attention of investors, business leaders, regulators and politicians. Whereas a Dollar, Yen, Yuan or Euro can be hold like a currency, they cannot be secured and transacted simply by itself. Individuals have to rely on third party intermediaries in order to transfer funds for them and in order to store them securely. Contrary to that, one cannot focus on Bitcoin as a currency without acknowledging that it is also a transaction system in itself and would not be able to function is one part of this duality is gone. In fact it is even more precise to look at Bitcoin as a decentralized transaction and financial services system, with a currency function being only one aspect of the technology. In this book: - Bitcoin; - Ripple; - cryptocurrency; - financial technology; - financial service; - virtual currency