Cryptocurrencies gained their greatest popularity after the global financial crisis of 2008 and the COVID-19 crisis, and since then their popularity has been growing. The research found that cryptocurrencies, despite challenges such as volatility and different legal frameworks, have brought a revolution in the financial world. Cryptocurrencies, based on a decentralized system, enable direct transactions between two parties via the internet, without the intermediation of financial institutions. The most famous among them is Bitcoin, which was introduced in 2008. All cryptocurrencies are based on blockchain technology, which provides security, transparency, and speed of transaction execution. However, the legal framework for cryptocurrencies varies from country to country, making their use complex. Without major legal regulations and preventing large oscillations and volatility, the replacement of cryptocurrencies with fiat currency is unlikely. Despite this, cryptocurrencies facilitate the international economy by reducing transaction costs and increasing financial inclusion, but it is difficult to predict whether cryptocurrencies like Bitcoin will be able to replace traditional payment methods given the unclear legal questions surrounding them. The limitation of this research is the different legal framework in different countries, which prevents defining a clear conclusion about the direction of development of a potential universal regulatory framework for regulating cryptocurrency transactions. Despite the challenges, cryptocurrencies and blockchain have an impact on the financial world.