trying to drop database but says database dosnt exists even thought I can use it

Question

Got this weird error happening I am trying to clean up my databases that I am not using. however when I try to drop mysql it says database dosnt exists, however I can use it!! weird or what?! any way for me to get rid of this database from my list.

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+
4 rows in set (0.00 sec)

mysql> use test;
Database changed
mysql> drop mysql;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'mysql' at line 1
mysql> drop database mysql;
ERROR 1146 (42S02): Table 'mysql.proc' doesn't exist
mysql> create database mysql;
ERROR 1007 (HY000): Can't create database 'mysql'; database exists
mysql> 

Answer 1

That's a special database containing users, etc. You shouldn't remove it and MySQL isn't letting you.