What are special character conversions, characters such as '\u0026amp', '\u003c', and '\u003e'?

Special characters are read as code, not as characters, as follows:

I'd like to know if there is a way to change the name of this code format and change the code to characters that we normally see.

The current encoding is euc-kr.

'\u0026amp' #&Ganada
'\u003c is me' # < is me
'\u003e is ' # > is 'nada'