Why put %'Author'% in a percentage?

Question

PHP

Hello! There is a variable (or how to call it) %'Author'% , why is it placed in %%, why can't it be made as a variable in $? Does %% have its own functions, for example, counting the number of characters in the displayed author name?

Answer 1

Such "variables" are used in configs (for example, yaml) or in the text, for example, if you want to dynamically substitute some piece of text, for example, %date% is replaced with the current date.

Answer 2

Perhaps you are dealing with a template engine and a template for it.