Core PHP is very basic PHP. It is used to create dynamic web pages. ... So it is very important to learn core or principle PHP programming to create dynamic web applications. You can see more about PHP from the official site of PHP Hypertext Preprocessor.
Laravel is a free, open-source PHP web framework, created by Taylor Otwell and intended for the development of web applications following the model–view–controller architectural pattern and based on Symfony.
CakePHP is an open-source web framework. It follows the model–view–controller approach and is written in PHP, modeled after the concepts of Ruby on Rails, and distributed under the MIT License.
CodeIgniter is an open-source software rapid development web framework, for use in building dynamic web sites with PHP.
WordPress is a free and open-source content management system based on PHP and MySQL. Features include a plugin architecture and a template system. It is most associated with blogging but supports other types of web content including more traditional mailing lists and forums.