Cryptography (which includes non-cryptology, cryptography, and cryptanalysis) is from the perspective of mathematical analysis of encryption. It is also used for secret communication, allowing the world to see an encrypted message if someone is listening to it, and not letting them know the real word. Only the recipient can read it. As you mentioned, you can “register” things using a similar scheme, but “pre-decrypt” (my term) is something, and other people who link your cryptographic key can show that you signed something.
So cryptography is used almost exclusively in security areas. You can only restrict those who have access to secret data. This is useful for sending messages to ensure that paid customers can install the software and be responsible (at least by trying to prevent people from “joking” with their phone).
It can also provide some security in other ways. Some “dark networks”, especially Freenet, do not censor information. Each user stores the data on their computer, so deleting it will not delete the data from the network. Once the report is downloaded, it may be almost impossible to delete it. In the case of illegal content, you may inadvertently put it on a computer. However, since it is encrypted, the judge should not be held responsible for storing the data on the computer, as it is impossible, if possible, to prove that your computer is receiving illegal content. Do not enter unintentionally unless you try to decipher it in other illegal ways.
With Bitcoin, you can also find cryptographic applications:
Tahoe-LAFS (and other encrypted file storage systems)
PGP / GPG (plain text encryption, you can send emails to people without reading the message)
Finally, I would say that single passwords can be a growing trend. I have a key to connect to the program every time I need a new password. Only 64,000 random passwords will be verified as “I am”, so the attacker will not be able to enter passwords, but will not be able to steal the password that he uses and reuses. Once applied, it can no longer be used.
Uses of cryptography
At the heart of what you’ve learned so far is the fact that cryptography is the art of storing and writing information only to those who need to see it. Hide from everyone else. Before the information age, cryptography was only used to ensure the secrecy of information. Encryption has been used to ensure the confidentiality of spy communications, military and diplomatic leaders. Egyptian hieroglyphs, spade passwords used by the Spartan Spaniards, plaster, and various complementary physical devices have been used throughout modern times throughout history. These devices underwent other changes when computers and electronic devices appeared, which helped a lot in cryptanalysis.