what is the php file extension ?

Question

PHP stands for ("hypertext preprocessor");

Answer 1

". php" obviously

Answer 2

.php contains the source code of php
for example :
.html contains html source code written in html

Answer 3

.php file extension is a hypertext preprocessor which means it is where all the main codes or source codes of a website is. i.e with the php file of any site u can have complete control over the site, in the file u can find the cpanel login i.e admin login e.t.c