Content
Traditional currencies have double payment (Double Spending) problems, such as cheque fraud in the non-digital era and credit card fraud in the digital era. In the Bitcoin system, the confirmation of each transaction needs to be broadcasted throughout the network and included in the Block before it can be truly confirmed. For every money spent, it is necessary to check the status of the last input transaction. The data is time-stamped and public, and BlockChain guarantees its security by huge computing power. Therefore, the Bitcoin system greatly reduces the risk of multiple currency payments to almost zero. By waiting for multiple block confirmations, the probability is reduced to zero. Generally, after 6 confirmations, it can be considered very safe. But for major payments that can affect your life, it is recommended to wait for 20 to 30 confirmations.
Anonymity
Anyone can easily generate a large number of private keys, public keys, and addresses. The address itself is anonymous, and the anonymity can be further improved through multiple address transactions. But this anonymity is not a certain degree of anonymity as the media advertised. Because Bitcoin transaction data is public, the flow of any funds can be tracked.
People who don't know Bitcoin have some concerns about its anonymity, such as worrying that it is more conducive to engaging in illegal business; people who know Bitcoin are distressed because of its pseudo-anonymity. Traditional currencies are also anonymous in consumption and are guaranteed by law. Most countries do not allow individuals to paint paper money.
The address itself is anonymous, but you can prove to the public that you own a Bitcoin address by signing a message with the private key corresponding to the address.