All types of encodings on websites, in e-mail messages, files and texts are needed for the same purpose - to save information in a binary representation familiar to the machine.
Imagine that you have a friend who, of all symbols, understands only zero and one. Since childhood, he does not know any letters or other numbers, and can read messages consisting exclusively of combinations of these two characters. How to communicate with him, how to say words to him, how to understand his answers are typical questions that you would have at the beginning of communication. The solution is as follows: make a table according to which each letter, symbol, number or punctuation mark will mean some sequence of zeros and ones. Start communicating with your friend according to this rule, encrypt all your words in binary form and decipher his answers.
But what if there are several dozen such people in the world? Everyone has their own friends, and everyone has come up with their own table of converting letters into numbers. If they meet each other, no one will understand anything, they all use different tabular languages of communication. For one, the letter "A" means - 000101, and for the other, this code corresponds to a question mark. A terrible confusion will arise, everyone will think that his interlocutor was mistaken or does not know how to speak.
What encodings exist
Let's list some of the most convenient and popular coding methods:
Unicode Transformation Format. Eight-bit Unicode representation. It was invented in 1992 and is still the gold standard for all software in the world. For Cyrillic, Unicode has two sections: Cyrillic and Cyrillic Supplement.
Created in 1990 specifically for the localization of the Microsoft Windows operating system. Cyrillic eight-bit encoding is the second most popular.
Eight-bit Cyrillic coding standard. If we remove the eighth bit from each character, we get a transcription of Russian letters into Latin. It is sometimes used in e-mail, but today it is rarely found on the Internet.