Privacy is the right of a person to select which parts of information about them can be accessed by others. Privacy violation by the government has been a hot topic for decades, but it became particularly controversial after Edward Snowden, a US intelligence contractor, has leaked information about PRISM, a clandestine surveillance program which the NSA used to spy on the US citizens without them consenting, or even knowing about it. Thus, it became clear to people that if they want to keep parts of their life truly private, they have to make an active effort. One of Bitcoin's advantages, at least initially, was the fact that all its transactions were anonymous. This is less true today, given the advances in Blockchain forensics that sometimes allow tracing Bitcoin transactions back to the people behind them.