phpMyAdmin is a feature-rich tool coded in PHP, that will present you with full control over a MySQL database. You could do practically everything - set up fields, rows and tables, delete them or alter their content, export or import an entire database or just a specific part of it, and execute MySQL commands. The tool is essential if you need to switch web hosting companies, as you may conveniently generate a full backup of a database in different formats (SQL, CSV, XML). You'll end up with just one file containing the whole content of the database, so you may download it from the present provider, upload it to the server of the new one and import it through the same tool on their end. Your site shall look exactly the same, simply because all script applications store their content in a database. With phpMyAdmin you can also quickly search and replace content of your choice across the entire website - a word, an expression or a link, for instance.