How in PHP (and it doesn't matter where) variables are stored, the variables themselves (names, maybe something else) are not values?

Question

Programming

I started with the PHP language, because. I am a PHP developer myself.
I know about the zval structure (php 5.6), how memory is allocated for it, what attributes this structure has.
Moreover, within the framework of the university, I wrote well in C, and then in C ++ 11 the Qt framework (I even wrote about 300 lines in assembler).
Those. what is a heap and a pointer, what is malloc / realloc I have an idea.
But, I get into a stupor when I think, how does PHP actually store the variable name itself? How does he know that such a variable exists (with such a name) in a given context, what does a typical data structure look like that stores a variable (not a value)?
I can't find the answer to this question on google.
Thank you.

Answer 1

Maybe this will clear things up.

Answer 2

https
://www.slideshare.net/ravirajforyou/how-php-works???