where or how are databases stored

just curious

i have a a shared hosting plan with a main account domain and several more added as addon domains which are stored in public html folder and each under another folder with their domain name

i know that if a make a complete backup of all folder through ftp or cpanel i get all files for pictures templates stylesheets and any other thing concerning layout and functions

but content is stored in other place and can only be exported as a database using something like phpmyadmin

but where

and in simple words why i need a special program like phpmyadmin to process all that content to be put in table shape.

where is my wordpress content and how is distributed in the hosting server.