First, I want to say that this is in no way to question the way somebody is writing. I'm just curious.
I have noticed that some Japanese people here use parentheses and an equals sign to clarify some word or to "define a variable". Example:
...very difficult to explain grammatically even to Japanese （＝日本人）.
I am pretty sure that most English speakers (or the part of the internet where I've spent most of my time) don't use the equals sign, so I came to the conclusion that this must be a Japanese thing.
Does this carry some other meaning than using plain parentheses in English? Also, is this used in official texts or is it just an informal way to clarify something?