mysql DB and Ports

[Hosney Osman]

Dear All
i am new member in mysql community and this is the first time using mysql
my question is
i am trying to connect tomcats application to mysql DB
i am create 2 datebases and grant all privileges to DB users
when i am trying to find the port of these DB i found the both are working in the same port 3306
i am using the following command to show thw DB port
mysql> use app1
mysql> show variables where variable_name = 'port';
i got the same result port number = 3306
is that OK
is that normal
i don't know

Thanks and Best Regards
Hosney Osman
[e-mail]