Completely Uninstall MySQL Server

I try to uninstall MySQL server using rpm -e --nodeps mysql mysql-server and seen that it is not completely remove. When I install MySQL server again. The databases and root password still remain. May you tell me how to remove MySQL Server completely include databases and password? I'm using CentOS 5.3

One more thing, What is this command mean?

mysqladmin -h server1.example.com -u root password yourrootsqlpassword

Last edited by k_oudom; 10-05-2009 at 08:15 PM.