MySQL and WordPress: Understanding How Databases Work

WordPress uses MySQL, an open source database management system, to store and retrieve all of your website’s information, from the content of your posts and pages to your comments, usernames and passwords. If you need to visualize it, think of your site’s database as a filing cabinet and MySQL as the company that made it. MySQL is a popular choice of database for web applications – Joomla! and Drupal also use it, and according to Wikipedia lots of high-profile companies like Google, Facebook, Twitter, Flickr and YouTube use it, too.

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