Digital currency refers to the alternative currency in the form of electronic money. Digital gold coins and cryptocurrency belong to digital currency. How to use digital currency: 1 Investors must first register their accounts, and at the same time obtain digital currency accounts and US dollars or other foreign exchange accounts. 2. Users can buy and sell digital currency with the money in their cash accounts, just like buying and selling stocks and futures. 3. The trading platform will sort the buying requests and selling requests according to the rules and start matching. If they meet the requirements, the transaction is completed. 4. Due to the difference between the purchase and sale quantities submitted by users, the purchase or sale request may be partially executed.

Digital currency is an unregulated digital currency, which is usually published and managed by developers and accepted and used by members of a specific virtual community. The European Banking Authority defines virtual currency as a digital representation of value. It is not issued by the central bank or authorities, nor is it linked to legal tender, but it can be transferred, stored or traded electronically as a means of payment because it is accepted by the public.

Digital currency can be regarded as a virtual currency based on node network and digital encryption algorithm. The core features of digital currency are mainly reflected in three aspects: 1. Because it comes from some open algorithms, digital currency has no issuer, so no one or organization can control its distribution; 2. Because the number of algorithm solutions is determined, the total amount of digital currency is fixed, which fundamentally eliminates the possibility of inflation caused by too much virtual currency; 3. Because the transaction process needs the approval of all nodes in the network, the transaction process in digital currency is secure enough.

The emergence of Bitcoin poses a great challenge to the existing monetary system. Although it belongs to virtual currency in a broad sense, it is essentially different from the virtual currency issued by network enterprises, so it is called digital currency. Digital currency is compared with electronic currency and virtual currency in terms of issuer, scope of application, number of issues, storage form, circulation mode, credit guarantee, transaction cost and transaction security.