What do you call this code in which characters such as these?

Actually the question in the title.
Here's an example line : https://gyazo.com/74835e9529e38ed1f203ea5b502b7b5f
I need to know how such a presentation of the Cyrillic alphabet is called on scientific ?
July 2nd 19 at 17:04
2 answers
July 2nd 19 at 17:06
July 2nd 19 at 17:08
Depends on what is "scientifically": string expression, Cyrillic or something else.

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