How PHP and MySQL Work Together in WordPress

WordPress uses a PHP/MySQL platform, which provides everything you need to create your own website and publish your own content dynamically, without knowing how to program those pages. In short, all your content is stored in a MySQL database in your hosting account.

Defining PHP and MySQL

PHP is a server-side scripting language for creating dynamic Web pages. When a visitor opens a page built in PHP, the server processes the PHP commands, or functions, and then sends the results to the visitor's browser.

MySQL is an open-source relational database management system (RDBMS) that uses Structured Query Language (SQL), the most popular language for adding, accessing, and processing data in a database. Think of MySQL as a big filing cabinet where all the content on your site is stored.

Figuring out how PHP and MySQL work together

Every time a visitor goes to your site to read your content, a request is made that is sent to a host server. The PHP programming language receives that request, makes a call to the MySQL database, obtains the requested information from the database, and then presents the requested information to your visitor via his web browser.

Content refers to the data stored in the MySQL database which includes blog posts, pages, comments, links, and options that were set up in the WordPress Dashboard. The theme (or design) you choose to use for your site isn't part of the database content. Themes files are considered the presentation layer and are essential to user friendly website display.

Theme files are part of the file system and aren't stored in the database. So creating and keeping a backup of any theme files that you're currently using are good ideas.

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