Operating environment: iPhone 13, iOS 15.3. 1 etc.
1. Open the settings and click the face ID and password.
2. Click to open the password. After entering the page, click Open Password.
3. Set the password, as shown. Enter the password to complete the operation.
Cryptographic synthesis
Password is a symbol compiled according to a specific law, which is used to transmit the information of both parties. In other words, a password is a series of symbols that hide the real content. It changes the information expressed by an open and standard information code into an information code that can't be read by anyone except the two communication parties through a transformation method. This unique information code is a password.
Cryptography is a science with a long history. In the war between ancient Greece and the Persian Empire, passwords were used to transmit secret information. In modern wars, the transmission of information and the command of war are inseparable from passwords, and so is the diplomatic struggle. Passwords are generally used for the confidentiality of information communication transmission and storage. With the development of computer and information technology, the development of cryptography is also very rapid, and its application field is also expanding.
Passwords are not only used for information encryption, but also for data information signature and security authentication. In this way, the application of cryptography is no longer limited to serving military and diplomatic struggles, but is widely used in social and economic activities. Nowadays, there has been a trend of socialization and personalization of password application in the world.
For example, cryptographic technology can be applied to e-commerce to identify the identities and commercial credits of both parties in online transactions and prevent "hackers" and fraud in online e-commerce; When it is applied to VAT invoices, it can prevent forgery and tampering, put an end to all kinds of acts of stealing, leaking, evading and cheating taxes by using VAT invoices, and greatly facilitate tax inspection.
When it is applied to the identification of bank checks, it can greatly reduce the financial crime of financial fraud by using fake checks; When applied to personal mobile communication, it greatly enhances the confidentiality of communication information and so on.