An administrator’s tool of sorts, phpMyAdmin is a PHP script meant installed at the server-level for giving admins the ability to interact with their MySQL databases directly. WordPress, for example, stores all of its information in the MySQL database and interacts with the database to generate information within your WordPress site.
A “raw” view of the data, tables and fields stored in the MySQL database would be impossible to understand or work with. phpMyAdmin makes it accessible through a graphic user interface, or GUI.
Warning
With great power comes great responsibility. phpMyAdmin allows you to interact with the database directly: it also lets you mess up the database directly. There is no “undo” or “undelete” in your database. Always use caution when working directly with your database using phpMyAdmin.