Bitcoin, the leader in cryptocurrencies, is gaining credibility and is emerging as a competitor to traditional currencies. A real threat for the euro and the dollar. The price of bitcoin, which has been on an upward curve for several months, soared by 20% in the following 48 hours. The internet currency has crossed the record value of 50,000 dollars driven by an unprecedented craze. The car manufacturer Tesla has just invested 1.5 billion dollars in bitcoin. This sum represents approximately 8% of the cash flow of Elon Musk's company. Last October, Square, the payment company created and run by Twitter boss Jack Dorsey, invested $50 million in bitcoin. The company MicroStrategy, which specializes in data analysis software, also invested significant amounts of money in bitcoin, in several installments, during 2020 and 2021. Last December, his boss Michael Saylor announced that his company owned 40,000 bitcoins. In January 2021, the famous investment fund BlackRock, the world's number one asset manager, affirmed its intention to include certain bitcoin derivatives in the list of assets that the fund could take in its portfolio. Also, in early February, BNY Mellon Bank announced the creation of a new division dedicated to cryptocurrencies. The American company PayPal, which has developed a globally successful payment solution, has unveiled its intention to accept bitcoin transactions on its platform. Mastercard has also just accepted cryptocurrency transactions on its network. Jack Dorsey, and the billionaire rapper Jay-Z, husband of the singer Beyoncé, have also just invested 500 bitcoins in this ambitious project that puts traditional state currencies such as the euro or the dollar in competition. “Bitcoin is a speculative asset. But it was designed as a currency from the start. It's a digital currency project,” recalls Odile Lakomski-Laguerre, lecturer in economic sciences at the University of Picardie. For her, bitcoin is now in the third phase of its evolution, a phase of credibility.