phpMyAdmin is a feature-rich tool developed in PHP, that will present you with total control over a MySQL database. You may do literally everything - set up fields, rows and tables, erase them or alter their data, export or import a whole database or only a particular part of it, and execute MySQL commands. The tool is very important when you need to switch hosting providers, simply because you could conveniently create a full backup of a database in a variety of formats (SQL, CSV, XML). You will end up with a single file containing the whole content of the database, so you can easily download it from the present provider, upload it to the hosting server of the new one and import it via the same tool on their end. Your site will look exactly the same, simply because all script apps store their content in a database. With phpMyAdmin you can also conveniently search and replace information of your choice across the whole web site - a word, a phrase or a link, for instance.