PHP is a scripting language for web development and is a server side language used for making interactive and dynamic web pages.The extension of these files is .php
A short code is
While Mysql is a RDBMS(Relational database) that is used for storing information and programs to access it values and info. It provides you security,manipulation,storage. It helps you to store values in form of tables.
Eg: Used in login/signup pages etc.