Since ancient days money is a means of payment. It started with a simple trade and evolved to coins, paper money and todays electronic money. Electronic money is one of the ways in which we can make our payments on the Internet. In today's era of fast evolving information tecnology, electronic money is slowly gaining importance. There are several types of e-money such as digital currencies, card payment, e-cash and many others. Besides from knowing the ways of payment via the Internet, it's also importnat to know how to safely carry out financial transactions. The conducted empirical research showed that one of the reasons for insufficient use of e-money lays in its uncertainty and not enough knowledge of its system of payment. Methods of protection include encrypting the traffic between the parties involved in cash transactions, checking the authenticity of both parties and preventing the abuse of the system. Procedures that help preventing the abuse of the system are cryptographic algorithms and many protocols which ensure the protection of electronic money, as well as participants in the transaction. Privacy and authenticity are important characteristics of electronic payment systems.