Core PHP is a very basic PHP programming language; It is used to create dynamic web pages.

Don’t worry about what a dynamic web page is, there are basically two types of dynamic and static web applications, but more on that later. Or actually Learn here.

Core PHP works without any additional libraries, which a PHP framework cannot, so it is very important to learn basic PHP programming to create dynamic web applications.

Core PHP uses the purest form of PHP script, a developer needs to know the language thoroughly in order to write clear and concise code using central PHP.