So you are using mysql as a database and want to control and work with it. Same here. We have all our own system mostly running on Linux and a lot of applications are using the mysql database. I also have a lot of customer using mysql so I need to be able to use it and work a lot with mysql.
You can ofcouse use the command line for a lot of things and many times I do use that. But some times a graphical tool is god to use, especially when you are converting old applications and need to jump between tables and getting an overview of a system.
When I was using my old machine under windows there was a program called EMS SQL Manager (comercial) so you had to by it but it was very good. So i was looking for a simmelar program under linux and came across phpmyadmin ofcouse.