I'm quite a beginner with AJAX, so references are welcome.
Is it possible to call for a specific PHP function from a PHP file (and not run the whole PHP file) with AJAX? If so, how?
Background: I have a button that I want with jQuery that onclick on it, a specific PHP function from some given PHP file would be called. I prefer to not create a whole new file to run the body of the function, because the PHP file that I want to run the code from is a big functionality file (a WordPress